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Automotive electronics - Honda charging system
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Peabody
Dec 7, 2016, 12:21:58 PM12/7/16
to
This may not be the appropriate place to post about this. If so, just ignore
it, and my apologies.
Honda has a dual-mode charging system for US models. When the headlights are
on, or any other combination of things that increases the amp draw through
the system to a certain point, the computer tells the alernator to put out
14.4V, or thereabouts. But at all other times the alternator puts out about
12.3V. This is done to increase gas mileage.
At my last oil change (2012 Civic), the dealer checked out everything,
including the battery. They said the battery was ok, but was only 57%
charged. It seems to me that this is a direct result of the charging
algorithm. Even if the battery was fully charged, which would be a resting
voltage of just under 12.7V, if the alternator is told to output only 12.3V,
then the battery will be providing all the needed current until it is
discharged down to that level, which should happen fairly quickly.
My understanding is that lead-acid batteries don't do well being partially
charged all the time, not to mention not having as many cranking amps
available as you might need. In fact, I replaced the original battery at
just under three years. Yet Honda has been doing this dual-mode thing
literally for decades. So perhaps I'm wrong about the effect of this system
on battery life.
The odd thing is - if you want the car to charge the battery, you DO NOT want
to shut off the lights, the fan, the radio, etc., because that will just
lower the alternator voltage to 12.3V, which won't charge the battery at all.
Instead, you want to turn on the headlights - because that will cause the
alternator to put out 14.4V, which WILL charge the battery. Can you spell
counterintuitive?
So one option is just to get a charger, and charge the battery overnight
maybe once a week. But another alternative is to modify the current-sensing
circuit so the computer thinks the lights are on even when they aren't, so
the alternator will stay at 14.4V all time - just like every other car in the
world does. But before going down that road, I need to be sure I understand
what, if anything, this Honda system is doing to the battery because the
modification, which is called the ELD bypass, is a real bear for my model
car.
And in case you were wondering, it appears that this Honda system doesn't
take into account at all the current charge state of the battery.
Well, I would appreciate some expert opinion on the effects of having the
battery be partially charged all the time. I've read several places online
that this promotes sulfation. But it's not clear. It's also not clear
whether a weekly full charge would undo the sulfation.
Thanks for any advice.
it, and my apologies.
Honda has a dual-mode charging system for US models. When the headlights are
on, or any other combination of things that increases the amp draw through
the system to a certain point, the computer tells the alernator to put out
14.4V, or thereabouts. But at all other times the alternator puts out about
12.3V. This is done to increase gas mileage.
At my last oil change (2012 Civic), the dealer checked out everything,
including the battery. They said the battery was ok, but was only 57%
charged. It seems to me that this is a direct result of the charging
algorithm. Even if the battery was fully charged, which would be a resting
voltage of just under 12.7V, if the alternator is told to output only 12.3V,
then the battery will be providing all the needed current until it is
discharged down to that level, which should happen fairly quickly.
My understanding is that lead-acid batteries don't do well being partially
charged all the time, not to mention not having as many cranking amps
available as you might need. In fact, I replaced the original battery at
just under three years. Yet Honda has been doing this dual-mode thing
literally for decades. So perhaps I'm wrong about the effect of this system
on battery life.
The odd thing is - if you want the car to charge the battery, you DO NOT want
to shut off the lights, the fan, the radio, etc., because that will just
lower the alternator voltage to 12.3V, which won't charge the battery at all.
Instead, you want to turn on the headlights - because that will cause the
alternator to put out 14.4V, which WILL charge the battery. Can you spell
counterintuitive?
So one option is just to get a charger, and charge the battery overnight
maybe once a week. But another alternative is to modify the current-sensing
circuit so the computer thinks the lights are on even when they aren't, so
the alternator will stay at 14.4V all time - just like every other car in the
world does. But before going down that road, I need to be sure I understand
what, if anything, this Honda system is doing to the battery because the
modification, which is called the ELD bypass, is a real bear for my model
car.
And in case you were wondering, it appears that this Honda system doesn't
take into account at all the current charge state of the battery.
Well, I would appreciate some expert opinion on the effects of having the
battery be partially charged all the time. I've read several places online
that this promotes sulfation. But it's not clear. It's also not clear
whether a weekly full charge would undo the sulfation.
Thanks for any advice.
Jim Thompson
Dec 7, 2016, 12:42:20 PM12/7/16
to
particularly in warmer climates/seasons.
The correct TC can be seen at...
<http://www.analog-innovations.com/SED/AlternatorRegulatorTC.pdf>
You may be able to buy an off-the-shelf unit to replace the Honda
original... depends on how the Honda is wired.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
jurb...@gmail.com
Dec 7, 2016, 4:03:33 PM12/7/16
to
>"At a constant 14.4V setpoint you risk overcharging the battery,
particularly in warmer climates/seasons."
Disagree. the most reliable cars I have seen generally charge at like 15.2 when cold, tapering off with temperature of course.
particularly in warmer climates/seasons."
You are in Arizona, here it gets down to 0F so we need these batteries charged up, bigtime. And the less the battery is charged the higher the freezing point of the electrolyte.
What you say might be alright for the climate where you are, but here even that 5W20 shi9t oil can get so thick it bogs the starter down, especially with the better oil pumps in the newer cars.
Another thing that might surprise you is that some cars actually pull more power to run than to start, a sharp contrast to the past. In a V6 you generally have three coils that put out more firing voltage at more current than the old style V8, plus you have six fuel injectors whose current drain is not trivial.
The regulation in the older cars when it comes to charging is that you would lose too much water and have to keep adding it to the battery. With the sealed batteries this is not an issue. Of course technically they are more likely to explode but I have not heard of it happening much. Plus the pressure they built up before the electrolyte re-absorbs the gases is really not more dangerous than the hydrogen they used to emit.
I think Honda made a mistake doing that. Once out of factory warranty I would find the wire that controls this and make it put out the full voltage all the time. Again, the climate does matter. In Texas or whatever you are probably fine, but in Wisconsin that is another story. You gotta have the starter motor pull that sludge through the oil pump as well as fire ten amps worth of fuel injection just to get started. And after that ordeal for the battery then the alternator only half ass charges ? Ill conceived idea to say the least.
Another thing is that since the late 1980s, cars have had kinda shitty alternators. My friend's brother in law had a car that needed a new one every two years or so, and where they put it you had to damnear pull the engine. And this was a GM product, I think the 3.4L "rat" engine.
Fuck all that, gimme a 1967 Chevy.
tom
Dec 7, 2016, 4:28:55 PM12/7/16
to
"Jim Thompson" <To-Email-Use-Th...@On-My-Web-Site.com> wrote in
message news:q9ig4c94hu35rqh4d...@4ax.com...
modern cars and trucks? That should be enough load to keep the charge
voltage normal.
Jim Thompson
Dec 7, 2016, 4:33:23 PM12/7/16
to
On Wed, 7 Dec 2016 16:29:00 -0500, "tom" <tmille...@verizon.net>
wrote:
I wouldn't know... my car is 11 years old and my pick-em-up truck is
16 ;-) Neither has "daylight headlamps" though the car does sense
dark and turns them on.
wrote:
16 ;-) Neither has "daylight headlamps" though the car does sense
dark and turns them on.
Peabody
Dec 7, 2016, 6:14:12 PM12/7/16
to
tom says...
> Don't the headlights stay on all the time (when in the
> auto mode) on most modern cars and trucks? That should
> be enough load to keep the charge voltage normal.
No. The daytime running lights, at least on my car, use a
lot less current than full headlights, and the voltage stays
at 12.3V. The running lights appear to use the high beam
filaments, but at much lower than normal current.
I just received my cigarette lighter voltmeter, and on a run
downtown and back it never came off low voltage unless I
turned on the headlights, even over 60mph and with the
heater fan on. I assume the rear window defroster might
switch it to 14.4V, and perhaps the A/C. But otherwise, if
you're driving around during the day in wintertime with just
the running lights on, it's going to be 12.3V all the time.
And that means the battery isn't fully charged. Ever.
> Don't the headlights stay on all the time (when in the
> auto mode) on most modern cars and trucks? That should
> be enough load to keep the charge voltage normal.
lot less current than full headlights, and the voltage stays
at 12.3V. The running lights appear to use the high beam
filaments, but at much lower than normal current.
I just received my cigarette lighter voltmeter, and on a run
downtown and back it never came off low voltage unless I
turned on the headlights, even over 60mph and with the
heater fan on. I assume the rear window defroster might
switch it to 14.4V, and perhaps the A/C. But otherwise, if
you're driving around during the day in wintertime with just
the running lights on, it's going to be 12.3V all the time.
And that means the battery isn't fully charged. Ever.
Peabody
Dec 7, 2016, 6:37:53 PM12/7/16
to
jurb...@gmail.com says...
> Disagree. the most reliable cars I have seen generally
> charge at like 15.2 when cold, tapering off with
> temperature of course.
It will be next summer before I can test this, but there's a
"thing" attached to the negative battery terminal in
addition to the ground cable. Could this be a temperature
sensor for the battery? Is the negative terminal the right
place to take this reading? So far, though, if it's high
voltage, it's exactly 14.4V. No variation.
> I think Honda made a mistake doing that. Once out of
> factory warranty I would find the wire that controls
> this and make it put out the full voltage all the time.
Honda uses an Electronic Load Detector (ELD) that's located
in the engine compartment fuse box. It's a strange looking
thing that has a slot all the way through it, and there's a
metal bar that goes through that slot. The entire current
load of the system goes though that bar, and the ELD must
have a coil surrounding the slot. The current induces a
corresponding current in the coil, and then some mystery
circuit in the ELD pulls down the 5VDC provided by the
computer via a pullup resistor so that the voltage indicates
the current load. The switching point appears to be about
2.1V. Below that, you get 14.4V from the alternator.
So the solution to this could be to just add a pulldown
resistor to that sending line so that it always reads below
2.1V, or perhaps a 2V zener to ground, or even three forward
biased diodes to ground would work. You can't just ground
it because then the computer will throw a code and turn on
the check-engine light.
The problem is figuring out which wire it is, and getting to
it.
> Fuck all that, gimme a 1967 Chevy.
Nah. Modern cars are really nice.
> Disagree. the most reliable cars I have seen generally
> charge at like 15.2 when cold, tapering off with
> temperature of course.
"thing" attached to the negative battery terminal in
addition to the ground cable. Could this be a temperature
sensor for the battery? Is the negative terminal the right
place to take this reading? So far, though, if it's high
voltage, it's exactly 14.4V. No variation.
> I think Honda made a mistake doing that. Once out of
> factory warranty I would find the wire that controls
> this and make it put out the full voltage all the time.
in the engine compartment fuse box. It's a strange looking
thing that has a slot all the way through it, and there's a
metal bar that goes through that slot. The entire current
load of the system goes though that bar, and the ELD must
have a coil surrounding the slot. The current induces a
corresponding current in the coil, and then some mystery
circuit in the ELD pulls down the 5VDC provided by the
computer via a pullup resistor so that the voltage indicates
the current load. The switching point appears to be about
2.1V. Below that, you get 14.4V from the alternator.
So the solution to this could be to just add a pulldown
resistor to that sending line so that it always reads below
2.1V, or perhaps a 2V zener to ground, or even three forward
biased diodes to ground would work. You can't just ground
it because then the computer will throw a code and turn on
the check-engine light.
The problem is figuring out which wire it is, and getting to
it.
> Fuck all that, gimme a 1967 Chevy.
tom
Dec 7, 2016, 6:48:00 PM12/7/16
to
"Jim Thompson" <To-Email-Use-Th...@On-My-Web-Site.com> wrote in
volts. The batteries last about six years.
I must always remember to unplug the GPS as the cig lighter outlets are
always on.
Seems like a bad idea to let the battery go down to 12.3 volts while
running.
tom
Dec 7, 2016, 6:49:57 PM12/7/16
to
"Peabody" <waybackNO...@yahoo.com> wrote in message
news:20161207-2...@Peabody.ssl.astraweb.com...
by monkeys episode.
bitrex
Dec 7, 2016, 7:00:59 PM12/7/16
to
the headlights or in the fender somewhere for the daytime running lamps.
That probably doesn't draw too much current.
Then the headlamps switch on after dark, and they're usually LED,
halogen, or some kind of xenon HID.
My less-than-1-year-old Volt has LEDs for the low beams and warmish
orange-yellow halogens for the high beams. I often get people flashing
me thinking my low beams are actually my high beams. The LEDs in
combination with the halogens are like rays from the Almighty himself.
kevin93
Dec 7, 2016, 10:14:42 PM12/7/16
to
On Wednesday, December 7, 2016 at 3:37:53 PM UTC-8, Peabody wrote:
> jurb...@gmail.com says...
>
> > Disagree. the most reliable cars I have seen generally
> > charge at like 15.2 when cold, tapering off with
> > temperature of course.
Modern "maintenance free" batteries can't tolerate that high a charging voltage - they'll gas too much and lose electrolyte.
> jurb...@gmail.com says...
>
> > Disagree. the most reliable cars I have seen generally
> > charge at like 15.2 when cold, tapering off with
> > temperature of course.
> It will be next summer before I can test this, but there's a
> "thing" attached to the negative battery terminal in
> addition to the ground cable. Could this be a temperature
> sensor for the battery? Is the negative terminal the right
> place to take this reading? So far, though, if it's high
> voltage, it's exactly 14.4V. No variation.
>
...
There is a fair amount around on the web about the Honda charging system:
For example <http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto_pres>.
The 12.3 volts does sound a bit low - that article states it should be 12.5-12.7V. That is not enough to charge the battery but will maintain it at 100% SOC after it has charged.
The higher voltage setting is to be able to recharge the battery under conditions when it will get discharged somewhat.
The Spark EV even had a separate mode of operation when the car was new to condition the battery correctly during the first few weeks of its life.
kevin
Peabody
Dec 12, 2016, 4:44:36 PM12/12/16
to
Peabody says...
> It will be next summer before I can test this, but
> there's a "thing" attached to the negative battery
> terminal in addition to the ground cable. Could this be
> a temperature sensor for the battery? Is the negative
> terminal the right place to take this reading?
I wanted to follow up on my own post in case anybody sees
this in the future. I still don't know what that "thing"
is, but its connector looked a bit crooked, as though it
wasn't connected properly, so I broke and remade the
connection.
And now everything is different. Well, the high voltage
point is still 14.4V, but it stays there for a while after
the engine is started, which it didn't do before, and now the
lower voltage point varies between 12.8V and 13.2V, whereas
before it was always 12.3 or 12.4V. Also, when I go downhill
with my foot off the gas, it shifts into 14.4V mode. I
guess that could be some kind of regenerative thing,
although, you know, this is a regular engine, not a hybrid.
Anyway, since I make a lot of short hops, I still may need
to put the charger on it now and then, but it looks like
it's behaving a lot better than it did.
I just wish if the connection wasn't good it had turned on
the CEL and thrown a code of some kind. If that had been
the case, this would have shown up at the dealership when I
bought the car, and I probably wouldn't have had to replace
the battery at three years. I'm sure the connection has been
bad for the five years since I bought the car.
And by the way, a really handy thing to have is a little
voltmeter that plugs into the cigarette lighter socket, and
displays the current charging voltage continuously. About
$6 on Ebay, or even less if you get one from China.
> It will be next summer before I can test this, but
> there's a "thing" attached to the negative battery
> terminal in addition to the ground cable. Could this be
> a temperature sensor for the battery? Is the negative
> terminal the right place to take this reading?
this in the future. I still don't know what that "thing"
is, but its connector looked a bit crooked, as though it
wasn't connected properly, so I broke and remade the
connection.
And now everything is different. Well, the high voltage
point is still 14.4V, but it stays there for a while after
the engine is started, which it didn't do before, and now the
lower voltage point varies between 12.8V and 13.2V, whereas
before it was always 12.3 or 12.4V. Also, when I go downhill
with my foot off the gas, it shifts into 14.4V mode. I
guess that could be some kind of regenerative thing,
although, you know, this is a regular engine, not a hybrid.
Anyway, since I make a lot of short hops, I still may need
to put the charger on it now and then, but it looks like
it's behaving a lot better than it did.
I just wish if the connection wasn't good it had turned on
the CEL and thrown a code of some kind. If that had been
the case, this would have shown up at the dealership when I
bought the car, and I probably wouldn't have had to replace
the battery at three years. I'm sure the connection has been
bad for the five years since I bought the car.
And by the way, a really handy thing to have is a little
voltmeter that plugs into the cigarette lighter socket, and
displays the current charging voltage continuously. About
$6 on Ebay, or even less if you get one from China.
Jim Thompson
Dec 12, 2016, 6:38:41 PM12/12/16
to
On Mon, 12 Dec 2016 15:44:27 -0600, Peabody
<waybackNO...@yahoo.com> wrote:
>Peabody says...
>
> > It will be next summer before I can test this, but
> > there's a "thing" attached to the negative battery
> > terminal in addition to the ground cable. Could this be
> > a temperature sensor for the battery? Is the negative
> > terminal the right place to take this reading?
It's at "ground", so best place for a sensor. The positive terminal
<waybackNO...@yahoo.com> wrote:
>Peabody says...
>
> > It will be next summer before I can test this, but
> > there's a "thing" attached to the negative battery
> > terminal in addition to the ground cable. Could this be
> > a temperature sensor for the battery? Is the negative
> > terminal the right place to take this reading?
can see short duration, but very high voltage spikes.
>
>I wanted to follow up on my own post in case anybody sees
>this in the future. I still don't know what that "thing"
>is, but its connector looked a bit crooked, as though it
>wasn't connected properly, so I broke and remade the
>connection.
>
>And now everything is different. Well, the high voltage
>point is still 14.4V, but it stays there for a while after
>the engine is started, which it didn't do before, and now the
>lower voltage point varies between 12.8V and 13.2V, whereas
>before it was always 12.3 or 12.4V. Also, when I go downhill
>with my foot off the gas, it shifts into 14.4V mode. I
>guess that could be some kind of regenerative thing,
>although, you know, this is a regular engine, not a hybrid.
>
That would fit better with my TC data from the '60's when I was
designing alternator regulators...
<http://www.analog-innovations.com/SED/AlternatorRegulatorTC.pdf>
kt77
Jul 3, 2017, 11:39:02 PM7/3/17
to
On Monday, December 12, 2016 at 1:44:36 PM UTC-8, Peabody wrote:
> Peabody says...
The Camry does not appear to have a smart charging system. The battery voltage reads 14.2 volts after a cold start but doesn't stay there for long. If restarted while still warm, the battery voltage is close to float voltage which would not replace the charge lost in starting. Another problem is the parasitic current drain which runs continuously.
Driving the car once every 7-10 days discharged the battery over a period of many months and the engine eventually failed to start. The specific gravity of the battery showed empty. After getting a jump start, the car ran normally although I discovered later that the charge level of the battery was being replaced very slowly.
I bought a Black & Decker 2A Battery Charger/Maintainer which eventually restored the battery to full charge. The specific gravity now measures 1.285. The interesting thing is that the full recovery took two weeks.
It looks like I will also have to connect the Charger/Maintainer periodically or just leave it connected. In Maintain Mode the voltage levels out at 13.68 volts which should be a safe Float Voltage.
I also plan to buy one of the voltage monitors that plugs into the accessory socket to keep an eye on the battery voltage.
> Peabody says...
>
> I wanted to follow up on my own post in case anybody sees
> this in the future.
>
This thread has provided me with a lot of helpful information. I have a 2016 Toyota Camry and the charging system has not been keeping up with infrequent use and short trips. As in the Honda, I think they are reducing alternator load to increase fuel economy.
> I wanted to follow up on my own post in case anybody sees
> this in the future.
>
The Camry does not appear to have a smart charging system. The battery voltage reads 14.2 volts after a cold start but doesn't stay there for long. If restarted while still warm, the battery voltage is close to float voltage which would not replace the charge lost in starting. Another problem is the parasitic current drain which runs continuously.
Driving the car once every 7-10 days discharged the battery over a period of many months and the engine eventually failed to start. The specific gravity of the battery showed empty. After getting a jump start, the car ran normally although I discovered later that the charge level of the battery was being replaced very slowly.
I bought a Black & Decker 2A Battery Charger/Maintainer which eventually restored the battery to full charge. The specific gravity now measures 1.285. The interesting thing is that the full recovery took two weeks.
It looks like I will also have to connect the Charger/Maintainer periodically or just leave it connected. In Maintain Mode the voltage levels out at 13.68 volts which should be a safe Float Voltage.
I also plan to buy one of the voltage monitors that plugs into the accessory socket to keep an eye on the battery voltage.
pcdh...@gmail.com
Jul 4, 2017, 6:52:58 PM7/4/17
to
>It looks like I will also have to connect the Charger/Maintainer
>periodically or just leave it connected. In Maintain Mode the
>voltage levels out at 13.68 volts which should be a safe Float Voltage.
How about getting a slightly smaller alternator pulley?
>periodically or just leave it connected. In Maintain Mode the
>voltage levels out at 13.68 volts which should be a safe Float Voltage.
Cheers
Phil Hobbs
k...@notreal.com
Jul 4, 2017, 8:23:55 PM7/4/17
to
Robert Baer
Jul 4, 2017, 8:35:31 PM7/4/17
to
k...@notreal.com
Jul 4, 2017, 9:09:03 PM7/4/17
to
Peabody
Jul 5, 2017, 12:15:32 AM7/5/17
to
kt77 says...
> I bought a Black & Decker 2A Battery Charger/Maintainer
> which eventually restored the battery to full charge.
> The specific gravity now measures 1.285. The interesting
> thing is that the full recovery took two weeks.
> It looks like I will also have to connect the
> Charger/Maintainer periodically or just leave it
> connected. In Maintain Mode the voltage levels out at
> 13.68 volts which should be a safe Float Voltage.
> I also plan to buy one of the voltage monitors that
> plugs into the accessory socket to keep an eye on the
> battery voltage.
Sounds like your car has problems similar to my Honda. I
think all the manufacturers try to get as much mileage as
they can, so they use the alternator as little as possible.
The problem is that the battery doesn't stay fully charged
that way, so it sulfates up and dies sooner.
I continue to try to deal with mine. I've been using the
charger every week or so, but recently decided to try
driving with the headlights on all the time. The alternator
puts out 14.4V all the time when the lights are on, and that
should keep the battery charged. I shouldn't have to do
that, and I found a Honda TSB that addresses this problem
for 2012 Civics like mine. They program new charging
parameters into the computer. My car is out of warranty,
but I'm going to see if I can get the dealer to flash the
new firmware at Honda's expense since we know the fault was
there on delivery of the car.
I definitely recommend one of those votage meters that plugs
into what used to be the cigarette lighter socket. It will
tell you the current charging voltage.
Basically, my understanding is that a lead-acid battery is
fully charged at about 12.6-12.7V, and that's what the computer
should keep it at. You can get by with less, but at the
cost of shorter battery life. But to keep the battery at
12.6V, the voltage regulator should NEVER go below
13.0-13.2V, and immediately after starting the engine it
should go to 14.4V for several minutes at least to recharge
the battery. As of now, the only way I know to at least get
that is to turn on the headlights. Oddly, turning on the AC
does not do that.
> I bought a Black & Decker 2A Battery Charger/Maintainer
> which eventually restored the battery to full charge.
> The specific gravity now measures 1.285. The interesting
> thing is that the full recovery took two weeks.
> It looks like I will also have to connect the
> Charger/Maintainer periodically or just leave it
> connected. In Maintain Mode the voltage levels out at
> 13.68 volts which should be a safe Float Voltage.
> I also plan to buy one of the voltage monitors that
> plugs into the accessory socket to keep an eye on the
> battery voltage.
think all the manufacturers try to get as much mileage as
they can, so they use the alternator as little as possible.
The problem is that the battery doesn't stay fully charged
that way, so it sulfates up and dies sooner.
I continue to try to deal with mine. I've been using the
charger every week or so, but recently decided to try
driving with the headlights on all the time. The alternator
puts out 14.4V all the time when the lights are on, and that
should keep the battery charged. I shouldn't have to do
that, and I found a Honda TSB that addresses this problem
for 2012 Civics like mine. They program new charging
parameters into the computer. My car is out of warranty,
but I'm going to see if I can get the dealer to flash the
new firmware at Honda's expense since we know the fault was
there on delivery of the car.
I definitely recommend one of those votage meters that plugs
into what used to be the cigarette lighter socket. It will
tell you the current charging voltage.
Basically, my understanding is that a lead-acid battery is
fully charged at about 12.6-12.7V, and that's what the computer
should keep it at. You can get by with less, but at the
cost of shorter battery life. But to keep the battery at
12.6V, the voltage regulator should NEVER go below
13.0-13.2V, and immediately after starting the engine it
should go to 14.4V for several minutes at least to recharge
the battery. As of now, the only way I know to at least get
that is to turn on the headlights. Oddly, turning on the AC
does not do that.
pcdh...@gmail.com
Jul 5, 2017, 8:11:21 AM7/5/17
to
>How does that help? The voltage regulator is in charge of things.
It is, assuming there's enough alternator output for it to be in regulation. Sounds like that's likely the problem.
Cheers
Phil Hobbs
Peabody
Jul 5, 2017, 11:48:17 AM7/5/17
to
Peabody says...
> Basically, my understanding is that a lead-acid battery
> is fully charged at about 12.6-12.7V, and that's what
> the computer should keep it at. You can get by with
> less, but at the cost of shorter battery life. But to
> keep the battery at 12.6V, the voltage regulator should
> NEVER go below 13.0-13.2V, and immediately after
> starting the engine it should go to 14.4V for several
> minutes at least to recharge the battery. As of now,
> the only way I know to at least get that is to turn on
> the headlights. Oddly, turning on the AC does not do
> that.
I just wanted to report that I was able to get my Honda
dealer to do the service bulletin 12-041 flash update that's
supposed to fix this problem for the 2012 Civic. That will
be done tomorrow.
But I suspect that allowing the battery to be less than
fully charged, without doing anything about it, is a
deliberate Honda practice on all their cars to keep mileage
up. If I understand how a battery and battery sulfation
works, there's no reason to ever have the alternator putting
out 12.4V, which my Honda does most of the time. That would
let the battery drop to 12.0-12.2V, which is roughly 50%
charged, not fully charged. And at that level it will
sulfate up and die much more quickly than if kept fully
charged. So I suspect I'm still going to have to drive with
the lights on after the SB is applied. But maybe it will
help some. My voltmeter will tell the tale.
However, if keeping the battery at 50% does not cause
sulfation, then I'm wrong, and Honda is right. But
everything I read says that's bad for the battery, and it
should be kept at 12.6V which is near 100%. If anyone knows
for sure about this, please post here.
> Basically, my understanding is that a lead-acid battery
> is fully charged at about 12.6-12.7V, and that's what
> the computer should keep it at. You can get by with
> less, but at the cost of shorter battery life. But to
> keep the battery at 12.6V, the voltage regulator should
> NEVER go below 13.0-13.2V, and immediately after
> starting the engine it should go to 14.4V for several
> minutes at least to recharge the battery. As of now,
> the only way I know to at least get that is to turn on
> the headlights. Oddly, turning on the AC does not do
> that.
dealer to do the service bulletin 12-041 flash update that's
supposed to fix this problem for the 2012 Civic. That will
be done tomorrow.
But I suspect that allowing the battery to be less than
fully charged, without doing anything about it, is a
deliberate Honda practice on all their cars to keep mileage
up. If I understand how a battery and battery sulfation
works, there's no reason to ever have the alternator putting
out 12.4V, which my Honda does most of the time. That would
let the battery drop to 12.0-12.2V, which is roughly 50%
charged, not fully charged. And at that level it will
sulfate up and die much more quickly than if kept fully
charged. So I suspect I'm still going to have to drive with
the lights on after the SB is applied. But maybe it will
help some. My voltmeter will tell the tale.
However, if keeping the battery at 50% does not cause
sulfation, then I'm wrong, and Honda is right. But
everything I read says that's bad for the battery, and it
should be kept at 12.6V which is near 100%. If anyone knows
for sure about this, please post here.
Jim Thompson
Jul 5, 2017, 11:53:16 AM7/5/17
to
US 'CAFE' fuel economy standards are forcing car manufacturers into
Rube Goldberg 'solutions'...
Recently was provided a 'loaner' of a new Infiniti Q50 while my
ancient, 'real car' (12 year old) Q45 was in for service.
This Q50 had only a 2L 4-banger engine (provided by Mercedes no less).
At each traffic light the engine is STOPPED with a jerk, then
restarted... feels like a diesel start (compressed air ?) :-(
What a disconcerting piece of crap!
(I informed the dealer I wouldn't be buying any Infiniti product until
they came back to providing a honking V-8 again, like my Q45. He
sighed, said he agreed.)
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Thinking outside the box... producing elegant solutions.
Jim Thompson
Jul 5, 2017, 11:56:30 AM7/5/17
to
charge...
<http://www.analog-innovations.com/SED/AlternatorRegulatorTC.pdf>
Also see my patents about alternator regulators.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Peabody
Jul 5, 2017, 2:05:56 PM7/5/17
to
Jim Thompson says...
> There's a 'little' TC issue that must be met to ensure
> proper charge...
> <http://www.analog-innovations.com/SED/AlternatorRegulat
orTC.pdf>
Thanks very much. Well I don't see anything on your graphs
anywhere near Honda's 12.4V. It looks like you have an
absolute minimum of 13V even at high temps. And I suspect
if my Honda followed that, there would be no problem.
Charging voltage aside, is the "off" voltage of a fully
charged battery also temperature dependent - assuming you
give it time to settle? So would the 12.6V I've been using
as a fully-charged voltage be lower at higher temps?
Is there a graph for that?
> There's a 'little' TC issue that must be met to ensure
> proper charge...
> <http://www.analog-innovations.com/SED/AlternatorRegulat
orTC.pdf>
anywhere near Honda's 12.4V. It looks like you have an
absolute minimum of 13V even at high temps. And I suspect
if my Honda followed that, there would be no problem.
Charging voltage aside, is the "off" voltage of a fully
charged battery also temperature dependent - assuming you
give it time to settle? So would the 12.6V I've been using
as a fully-charged voltage be lower at higher temps?
Is there a graph for that?
kt77
Jul 5, 2017, 3:37:15 PM7/5/17
to
Thanks Peabody and all others for your comments.
My problem with the 2016 Camry was probably the result of driving the car only once every week or two without any long trips. That assumes that the voltage regulator has been working as intended. The charging system might have been designed assuming several trips per week and a mix of short and long trips.
The parasitic current drain likely becomes a factor with infrequent use. If the parasitic current drain was 0.02 Amps, you would have 14.4 Amp Hours per month. A fully charged battery in new condition could be as low as 42 Amp Hours.
The voltage monitor does sound like an excellent idea. Using the accessory socket, the voltage reading could be a little low in some cars depending on the wiring. Other loads could increase the E=IR voltage drop.
The Toyota Manual includes a table showing battery voltage at different charge levels. The table shows 12.6 to 12.8 volts for Full Charge, 12.2 to 12.4 volts for Half Charge, and 11.8 to 12.0 Volts for Discharged.
Those values assume 68 degrees F and engine off for at least 20 minutes to remove surface charge. Personally, I think you have to wait quite a bit longer than 20 minutes. The Toyota Manual also mentions that charge current is 5 Amps maximum. I wonder if that is a design goal under high electrical load at a specified engine RPM.
I've also heard mention of a headlight test with the engine off. After one minute, the voltage should be above 12 volts. My battery also passes that test with the high beams turned on.
I checked the specific gravity of my battery one more time and was surprised that it now reads 1.295. That is apparently about as high as it can get. The Black & Decker 2A Charger/Maintainer continues to charge the battery very slowly even at the float voltage of 13.68 volts. It appears that one deep discharge did not damage the battery.
My problem with the 2016 Camry was probably the result of driving the car only once every week or two without any long trips. That assumes that the voltage regulator has been working as intended. The charging system might have been designed assuming several trips per week and a mix of short and long trips.
The parasitic current drain likely becomes a factor with infrequent use. If the parasitic current drain was 0.02 Amps, you would have 14.4 Amp Hours per month. A fully charged battery in new condition could be as low as 42 Amp Hours.
The voltage monitor does sound like an excellent idea. Using the accessory socket, the voltage reading could be a little low in some cars depending on the wiring. Other loads could increase the E=IR voltage drop.
The Toyota Manual includes a table showing battery voltage at different charge levels. The table shows 12.6 to 12.8 volts for Full Charge, 12.2 to 12.4 volts for Half Charge, and 11.8 to 12.0 Volts for Discharged.
Those values assume 68 degrees F and engine off for at least 20 minutes to remove surface charge. Personally, I think you have to wait quite a bit longer than 20 minutes. The Toyota Manual also mentions that charge current is 5 Amps maximum. I wonder if that is a design goal under high electrical load at a specified engine RPM.
I've also heard mention of a headlight test with the engine off. After one minute, the voltage should be above 12 volts. My battery also passes that test with the high beams turned on.
I checked the specific gravity of my battery one more time and was surprised that it now reads 1.295. That is apparently about as high as it can get. The Black & Decker 2A Charger/Maintainer continues to charge the battery very slowly even at the float voltage of 13.68 volts. It appears that one deep discharge did not damage the battery.
Peabody
Jul 5, 2017, 4:49:29 PM7/5/17
to
kt77 says...
> My problem with the 2016 Camry was probably the result
> of driving the car only once every week or two without
> any long trips. That assumes that the voltage regulator
> has been working as intended. The charging system might
> have been designed assuming several trips per week and a
> mix of short and long trips.
I have a similar problem in that my gym is .75 miles from my
house. That's not really far enough to recharge the
battery, even if the regulator is at 14.4V. So if I do too
many of those trips, with no longer ones in between, then
I'm going to have to use the charger to bring it back up.
I've never had a good feel for how long it actually takes to
recharge fully after one engine start if the alternator is
at max. My Civic starts very easily, so I wonder if it
needs more than maybe 15 minutes to recoup. Could even be
less I guess.
> The voltage monitor does sound like an excellent idea.
> Using the accessory socket, the voltage reading could be
> a little low in some cars depending on the wiring. Other
> loads could increase the E=IR voltage drop.
Yes, I'd recommend you get one (Ebay - $10 or less), if
for no other reason than you'll never have to wonder
what's going on. And it might even surprise you. The
supply to that socket goes through the ignition switch, but
other than that I don't think there's much to alter the
readings. It's going to be wired pretty strongly because of
what it's supposed to be able to do. My monitor reads 14.4V
with the headlights on, and that's right on spec. And the
monitor itself is digital, and doesn't draw any significant
current.
> My problem with the 2016 Camry was probably the result
> of driving the car only once every week or two without
> any long trips. That assumes that the voltage regulator
> has been working as intended. The charging system might
> have been designed assuming several trips per week and a
> mix of short and long trips.
house. That's not really far enough to recharge the
battery, even if the regulator is at 14.4V. So if I do too
many of those trips, with no longer ones in between, then
I'm going to have to use the charger to bring it back up.
I've never had a good feel for how long it actually takes to
recharge fully after one engine start if the alternator is
at max. My Civic starts very easily, so I wonder if it
needs more than maybe 15 minutes to recoup. Could even be
less I guess.
> The voltage monitor does sound like an excellent idea.
> Using the accessory socket, the voltage reading could be
> a little low in some cars depending on the wiring. Other
> loads could increase the E=IR voltage drop.
for no other reason than you'll never have to wonder
what's going on. And it might even surprise you. The
supply to that socket goes through the ignition switch, but
other than that I don't think there's much to alter the
readings. It's going to be wired pretty strongly because of
what it's supposed to be able to do. My monitor reads 14.4V
with the headlights on, and that's right on spec. And the
monitor itself is digital, and doesn't draw any significant
current.
kt77
Jul 5, 2017, 5:47:19 PM7/5/17
to
On Wednesday, July 5, 2017 at 1:49:29 PM UTC-7, Peabody wrote:
> I've never had a good feel for how long it actually takes to
> recharge fully after one engine start if the alternator is
> at max. My Civic starts very easily, so I wonder if it
> needs more than maybe 15 minutes to recoup. Could even be
> less I guess.
I've also thought about the charge lost in starting. My car starts in a second or less in the summer, so I estimate that to be no more than 200 Amp Seconds. A 42 Amp Hour battery would equate to 151200 Amp Seconds although you would have to derate that value when discharging at high current. If I'm doing the calculation correctly a single start might consume less than 1% of battery capacity at full charge.
> I've never had a good feel for how long it actually takes to
> recharge fully after one engine start if the alternator is
> at max. My Civic starts very easily, so I wonder if it
> needs more than maybe 15 minutes to recoup. Could even be
> less I guess.
It sounds as though your wiring is fine. I'll probably try turning the fan on high to see if the voltage reading changes. Right now I'm considering the INNOVA 3721 Battery and Charging System Monitor available on Amazon.
I just measured my battery voltage 20 hours after disconnecting the charger/maintainer and it read 12.82 volts.
Jim Thompson
Jul 5, 2017, 6:23:24 PM7/5/17
to
necessary to supply current TO the battery, so I suspect, but don't
know absolutely that the battery should show voltage equivalent to
that IF at the proper temperature.
k...@notreal.com
Jul 5, 2017, 9:42:35 PM7/5/17
to
>>How does that help? The voltage regulator is in charge of things.
>
>It is, assuming there's enough alternator output for it to be in regulation. Sounds like that's likely the problem.
Doesn't to me. It seems the charging system is trying to be too cute
>
>It is, assuming there's enough alternator output for it to be in regulation. Sounds like that's likely the problem.
to save .001MPG.
kt77
Jul 6, 2017, 12:35:46 AM7/6/17
to
Here is some information on adjusting battery charge voltage relative to temperature.
http://www.trojanbattery.com/Tech-Support/FAQ/Temperature.aspx
"For every 10 degrees above 80F, subtract .028 volt per cell from the charger voltage setting."
"Example: A 12 volt battery at 90F. The recommended charging voltage (at 80F) is 14.60 volts. The adjusted charging voltage is 14.60 - (6 cells x .028vpc) = 14.43 volts."
The next link mentions 12.4 volts as a key level to maintain battery life.
https://www.optimabatteries.com/en-us/experience/2010/12/what-normal-parasitic-draw
"The key to long life for any battery is to make sure battery voltage doesn't drop below 12.4 volts. The combination of a significant parasitic draw and long periods of non-use can easily cause voltage to drop below 12.4 volts. When that happens, sulfation begins to diminish both capacity and performance. That is why vehicles that only see weekend or occasional use (this includes boat owners) should have their batteries maintained with a quality battery tender or maintainer."
http://www.trojanbattery.com/Tech-Support/FAQ/Temperature.aspx
"For every 10 degrees above 80F, subtract .028 volt per cell from the charger voltage setting."
"Example: A 12 volt battery at 90F. The recommended charging voltage (at 80F) is 14.60 volts. The adjusted charging voltage is 14.60 - (6 cells x .028vpc) = 14.43 volts."
The next link mentions 12.4 volts as a key level to maintain battery life.
https://www.optimabatteries.com/en-us/experience/2010/12/what-normal-parasitic-draw
"The key to long life for any battery is to make sure battery voltage doesn't drop below 12.4 volts. The combination of a significant parasitic draw and long periods of non-use can easily cause voltage to drop below 12.4 volts. When that happens, sulfation begins to diminish both capacity and performance. That is why vehicles that only see weekend or occasional use (this includes boat owners) should have their batteries maintained with a quality battery tender or maintainer."
kt77
Jul 12, 2017, 2:15:02 PM7/12/17
to
On Wednesday, July 5, 2017 at 1:49:29 PM UTC-7, Peabody wrote:
> I've never had a good feel for how long it actually takes to
> recharge fully after one engine start if the alternator is
> at max. My Civic starts very easily, so I wonder if it
> needs more than maybe 15 minutes to recoup. Could even be
> less I guess.
I've seen several threads discussing the time to recharge a battery after starting and estimates range from 2-30 minutes.
> recharge fully after one engine start if the alternator is
> at max. My Civic starts very easily, so I wonder if it
> needs more than maybe 15 minutes to recoup. Could even be
> less I guess.
One method is to first estimate the cranking time and amperage. Assume that you crank the starter for two seconds at an average current of 250 amps which represents 500 amp-seconds. The charge current is hard to estimate but might be in the range of 5-30 amps.
If we use an average charge current of 5 amps, we could replace the 500 amp-seconds discharged from the battery in 100 seconds if no energy is lost. The efficiency of a lead acid battery is considered to be 50-90% with the lowest efficiency seen near full charge. If we assume 50% efficiency, the recharge would take 200 seconds or a little over 3 minutes.
It sounds as though the Honda Dual-Mode Charging System is not keeping the battery fully charged. It's possible that the battery stays in a range where the state of charge is perhaps 60-70%. In that case, the battery is probably never recharged to 100% of capacity.
There are probably many other factors involved. Here is an excellent article that discusses surface charge in a lead acid battery that is worth reading.
http://www.smartgauge.co.uk/surf_chg.html
"The first thing to remember is that the process of storing energy in a battery is a chemical reaction. The idea is to turn as much as possible of the lead sulphate (which form the plates of a flat battery) into lead and lead dioxide (which form the plates of a fully charged battery). But this chemical reaction is actually quite slow."
"Initially the chemical reaction only takes place on the surface of the plates, where they are in contact with the electrolyte. It takes some time for this chemical reaction to start to penetrate deep into the plates. This is effectively the "surface charge"."
"It can mean that a very low charge current is going into the batteries because the surfaces of the plates are fully charged. But wait some time, and the surface of the plates will become slightly discharged. In effect they have discharged into the "deeper innards" of the plates. This is effectively what limits the speed at which lead acid batteries can be charged."
Steve Wilson
Jul 12, 2017, 2:53:54 PM7/12/17
to
kt77 <kawi...@gmail.com> wrote:
> It sounds as though the Honda Dual-Mode Charging System is not keeping
> the battery fully charged. It's possible that the battery stays in a
> range where the state of charge is perhaps 60-70%. In that case, the
> battery is probably never recharged to 100% of capacity.
> There are probably many other factors involved. Here is an excellent
> article that discusses surface charge in a lead acid battery that is
> worth reading.
> http://www.smartgauge.co.uk/surf_chg.html
Thank you for the excellent and very interesting posts on this topic. I
> It sounds as though the Honda Dual-Mode Charging System is not keeping
> the battery fully charged. It's possible that the battery stays in a
> range where the state of charge is perhaps 60-70%. In that case, the
> battery is probably never recharged to 100% of capacity.
> There are probably many other factors involved. Here is an excellent
> article that discusses surface charge in a lead acid battery that is
> worth reading.
> http://www.smartgauge.co.uk/surf_chg.html
also have a chronic problem with keeping the battery charged on short
trips. I use a Scangauge to monitor the battery voltage and compare it to
a 5-digit voltmeter plugged into the 12 volt accessory socket. The
Scangauge reads about 0.1 volt low.
I had a 2001 Ford Taurus that insisted on keeping the alternator output
at 13.5 to 14.0 volts. This failed to keep the battery charged and it
would sulphate. After losing three batteries in three years ($450 total),
I decided to remove the battery after each trip, bring it inside and hook
it up to a lab supply that current limited at 5 Amp.
Obviously the battery was charged a bit on the trip home, but as I raised
the voltage, very little current would flow until I reached almost 14.5
volts. Then the supply would rapidly current limit at 5 Amp. All this
happened within about 0.1 to 0.2 volts. The current rise was very steep.
It only took a few minutes for the current to taper off down to 0.05 Amp
where it would stay until the next time I needed the car.
My next car is a 2003 Ford Focus. I had to install a new battery shortly
after purchasing the car. It has been happier with short trips but it has
a very strange algorithm to charge the battery. In the winter when the
temperatures are around -20C, the alternator voltage ranges from 14.5 to
15.0 volts. In the summer, it ranges from 14.0 to 14.5 volts. I haven't
taken the battery out and put it in the charger, but so far the car
starts in 1 or 2 seconds summer or winter. Even on the coldest days there
is no indication the battery is low. However, when I measure the voltage
using the accessory output after the car has sit idle, the no load
voltage measures 12.1 volt in the winter and 12.3 volts in the summer.
I have turned off all loads such as interior lights, and I have added a
separate relay that disables the door locks when I insert the ignition
key. This draws 50 mA and I can see the battery voltage decreasing
slowly, but it stops when I remove the key. So I know my low voltage
readings are the open circuit battery voltage and not caused by an
external load.
If you look at the various battery sites, these voltages indicate the
battery has very little charge and should be sulphating. But it seems to
work fine, so I'll leave it alone and keep monitoring the situation.
Thanks for the interesting information. I'll continue watching for your
posts so see if I can find any information that could explain these
strange readings.
Peabody
Jul 12, 2017, 5:32:57 PM7/12/17
to
kt77 says...
> It sounds as though the Honda Dual-Mode Charging System
> is not keeping the battery fully charged. It's possible
> that the battery stays in a range where the state of
> charge is perhaps 60-70%. In that case, the battery is
> probably never recharged to 100% of capacity.
That appears to be the case. And I think that's a charge
level that would never give problems in terms of being
able to start the engine. In my case, it maintained the
battery at about 12.2V (measured in the morning after
resting overnight), which I think is about a 50% charge, and
I never had a problem starting - until the battery actually
died, which happened at under three years. So while the
Honda system may give them great mileage numbers, and work
ok for starting, the lower average charge level results in
increased sulfation that significantly reduces battery life.
Last week I took my Civic into the dealer and had a
heart-to-heart talk with the service manager about a
technical sevice bulletin that I was never advised about.
It provides for flashing new charging parameters into the
computer. They agreed to apply the TSB at no charge to me,
and since then, the alternator has spent most of the time at
14.4V. But more important, when I measure battery voltage
in the morning, it's around 12.52V, which I think is
probably ok. Not 100% charged, but I think close enough.
I think a better approach, which may be in effect on newer
models, is to allow the computer to completely disconnect
the battery from the charging system after the car has been
started and the battery brought back up to a full charge.
Then you could run the alternator at 12.0V, or even less,
but the battery wouldn't see that. That would be very
efficient, but leave the battery fully charged, which is
what you want.
Or even better, there's the new alternative car battery
that's made up of lithium batteries, supercapacitors to
provide the cranking amps, and electronics to charge the
capacitors. I don't know if it's ready for prime time, but
looks interesting, and, you know, the kind of thing we
should be able to do now, with all the environmental and
weight benefits.
https://www.youtube.com/watch?v=BsP0QGX1Qiw
http://www.getohm.com/
> It sounds as though the Honda Dual-Mode Charging System
> is not keeping the battery fully charged. It's possible
> that the battery stays in a range where the state of
> charge is perhaps 60-70%. In that case, the battery is
> probably never recharged to 100% of capacity.
level that would never give problems in terms of being
able to start the engine. In my case, it maintained the
battery at about 12.2V (measured in the morning after
resting overnight), which I think is about a 50% charge, and
I never had a problem starting - until the battery actually
died, which happened at under three years. So while the
Honda system may give them great mileage numbers, and work
ok for starting, the lower average charge level results in
increased sulfation that significantly reduces battery life.
Last week I took my Civic into the dealer and had a
heart-to-heart talk with the service manager about a
technical sevice bulletin that I was never advised about.
It provides for flashing new charging parameters into the
computer. They agreed to apply the TSB at no charge to me,
and since then, the alternator has spent most of the time at
14.4V. But more important, when I measure battery voltage
in the morning, it's around 12.52V, which I think is
probably ok. Not 100% charged, but I think close enough.
I think a better approach, which may be in effect on newer
models, is to allow the computer to completely disconnect
the battery from the charging system after the car has been
started and the battery brought back up to a full charge.
Then you could run the alternator at 12.0V, or even less,
but the battery wouldn't see that. That would be very
efficient, but leave the battery fully charged, which is
what you want.
Or even better, there's the new alternative car battery
that's made up of lithium batteries, supercapacitors to
provide the cranking amps, and electronics to charge the
capacitors. I don't know if it's ready for prime time, but
looks interesting, and, you know, the kind of thing we
should be able to do now, with all the environmental and
weight benefits.
https://www.youtube.com/watch?v=BsP0QGX1Qiw
http://www.getohm.com/
kt77
Jul 13, 2017, 1:36:04 AM7/13/17
to
On Wednesday, July 12, 2017 at 2:32:57 PM UTC-7, Peabody wrote:
> They agreed to apply the TSB at no charge to me,
> and since then, the alternator has spent most of the time at
> 14.4V. But more important, when I measure battery voltage
> in the morning, it's around 12.52V, which I think is
> probably ok. Not 100% charged, but I think close enough.
The alternator voltage at 14.4 volts should make a big difference. I just found some information stating that you need 14.2-14.5 volts for a car battery to accept a reasonable charge current in amperes. That fits in with the information just provided by Steve.
> They agreed to apply the TSB at no charge to me,
> and since then, the alternator has spent most of the time at
> 14.4V. But more important, when I measure battery voltage
> in the morning, it's around 12.52V, which I think is
> probably ok. Not 100% charged, but I think close enough.
I drove fifteen miles today watching my new INNOVA 3721 Voltage Monitor. The voltage started out just below 14.2 volts and stayed above 14.0 volts for the next ten minutes. As the engine warmed up, the alternator voltage dropped but stayed in the range of 13.5 volts to 13.95 volts.
I'll check the battery voltage in the morning to see how things look. As a reference point, my battery charger/maintainer brought the battery up to the point where it read 12.82 volts after the surface charge had dissipated.
If you would like to confirm your state of charge, you could check the specific gravity assuming your battery has removable caps. I'm using a hydrometer that is at least 50 years old. My battery was slowly restored by the charger/maintainer and the specific gravity leveled off at 1.295 which is quite high. Remember that sulfuric acid is dangerous and eye protection should be used.
Over the last week I captured some data that should be useful when my car is not driven for a week or more. The battery voltage drifted down from 12.82 volts at a rate of about 0.015 volts per day. If that rate is maintained, the battery voltage would only drop to 12.5 volts after 20 days.
It does appear that my car is quite light in terms of charging. A battery will charge at 13.8 volts but a full charge would take a long time. I think the recharge time estimate for my car should assume a charge current that is only a fraction of an ampere.
mako...@yahoo.com
Jul 13, 2017, 2:41:17 PM7/13/17
to
>
> I think a better approach, which may be in effect on newer
> models, is to allow the computer to completely disconnect
> the battery from the charging system
But the car is now designed by politicians rather than engineers.
m
kt77
Jul 14, 2017, 6:15:55 PM7/14/17
to
Here is a new data point that might be of interest. Yesterday I reconnected my Black & Decker 2 amp battery charger/maintainer to top off the battery. I happened to notice that the voltage under charge read 14.24 volts which is actually a very significant number.
Charging at a current above a few amperes can only take place at 14.2 volts and higher which is consistent with my reading. It also suggests that my charge current while driving will be very limited with the alternator output in the range of 13.5 volts to 14.18 volts. The only exception might be after starting the engine when there is no surface charge on the battery plates. The voltage differential between alternator and battery would be higher for a period of time and I would expect the charge current to be higher and then decline as surface charge builds up.
It looks as though my drive on Wednesday did an acceptable job charging the battery with the voltage at 12.85 volts the following morning. The Black & Decker charger/maintainer charges to a somewhat higher level. I measured 12.88 volts this afternoon which was 22 hours after disconnecting the charger.
I'll also pass along a link to an amateur radio website with a lot of useful information. See the quoted text below which should be taken in the context of the 1970s.
https://www.w8ji.com/battery_and_charging_system.htm
"Since a 12 volt battery has six cells, any 12 volt lead-acid battery needs at least 13.8 volts to start to charge. This voltage will be enough to fully charge or maintain the battery on a trickle charge, but charging time will be very long at 13.8 volts."
"To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts."
"Less than 14.3 would be a "weak" alternator or regulator."
"When running at a normal slow cruising engine RPM, the voltage across the battery terminals should stay over 14.3 volts even with full load."
Charging at a current above a few amperes can only take place at 14.2 volts and higher which is consistent with my reading. It also suggests that my charge current while driving will be very limited with the alternator output in the range of 13.5 volts to 14.18 volts. The only exception might be after starting the engine when there is no surface charge on the battery plates. The voltage differential between alternator and battery would be higher for a period of time and I would expect the charge current to be higher and then decline as surface charge builds up.
It looks as though my drive on Wednesday did an acceptable job charging the battery with the voltage at 12.85 volts the following morning. The Black & Decker charger/maintainer charges to a somewhat higher level. I measured 12.88 volts this afternoon which was 22 hours after disconnecting the charger.
I'll also pass along a link to an amateur radio website with a lot of useful information. See the quoted text below which should be taken in the context of the 1970s.
https://www.w8ji.com/battery_and_charging_system.htm
"Since a 12 volt battery has six cells, any 12 volt lead-acid battery needs at least 13.8 volts to start to charge. This voltage will be enough to fully charge or maintain the battery on a trickle charge, but charging time will be very long at 13.8 volts."
"To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts."
"Less than 14.3 would be a "weak" alternator or regulator."
"When running at a normal slow cruising engine RPM, the voltage across the battery terminals should stay over 14.3 volts even with full load."
Steve Wilson
Jul 14, 2017, 6:48:46 PM7/14/17
to
kt77 <kawi...@gmail.com> wrote:
> Charging at a current above a few amperes can only take place at 14.2
> volts and higher which is consistent with my reading. It also suggests
> that my charge current while driving will be very limited with the
> alternator output in the range of 13.5 volts to 14.18 volts. The only
> exception might be after starting the engine when there is no surface
> charge on the battery plates. The voltage differential between
> alternator and battery would be higher for a period of time and I
> would expect the charge current to be higher and then decline as
> surface charge builds up.
>
> It looks as though my drive on Wednesday did an acceptable job
> charging the battery with the voltage at 12.85 volts the following
> morning.
Thanks for the new information and the link. It seems your infomation is
> Charging at a current above a few amperes can only take place at 14.2
> volts and higher which is consistent with my reading. It also suggests
> that my charge current while driving will be very limited with the
> alternator output in the range of 13.5 volts to 14.18 volts. The only
> exception might be after starting the engine when there is no surface
> charge on the battery plates. The voltage differential between
> alternator and battery would be higher for a period of time and I
> would expect the charge current to be higher and then decline as
> surface charge builds up.
>
> It looks as though my drive on Wednesday did an acceptable job
> charging the battery with the voltage at 12.85 volts the following
> morning.
very consistent about charging voltages. However, from your previous
post:
"I drove fifteen miles today watching my new INNOVA 3721 Voltage Monitor.
The voltage started out just below 14.2 volts and stayed above 14.0 volts
for the next ten minutes. As the engine warmed up, the alternator
This is similar to the readings I got on my Taurus alternator. However,
this killed the battery in less than a year. I went through three
batteries before I finally decided that Ford had no clue about charging
lead-acid batteries.
In your case, you measured 12.85 volts after your drive. I don't see how
that can happen with only 13.5 volts to 13.95 volts from the alternator.
That is what killed my batteries.
More mysteries to unravel...
kt77
Jul 15, 2017, 5:32:51 PM7/15/17
to
On Friday, July 14, 2017 at 3:48:46 PM UTC-7, Steve Wilson wrote:
>
> In your case, you measured 12.85 volts after your drive. I don't see how
> that can happen with only 13.5 volts to 13.95 volts from the alternator.
>
I also was surprised at the charge level the day after driving the car. The battery which is quite new had been fully charged with the battery maintainer. The engine starts in less than a second and the voltage rises to 14.18 volts after a cold start. The charge current could average 1 ampere over the next 5-7 minutes which could restore the charge. However, I also had two warm starts on that trip and the voltage stays under 14 volts. A battery will still charge above 13.6 volts but at very low current. It may be that the trip was long enough to restore the charge lost in starting. There may be one other factor and that is the loss of surface charge when starting. The lower battery voltage at that time might initially allow a reasonable charge current to flow while at 13.8-13.9 volts. The key may be the differential between alternator voltage and open circuit battery voltage.
>
> In your case, you measured 12.85 volts after your drive. I don't see how
> that can happen with only 13.5 volts to 13.95 volts from the alternator.
>
You mentioned something interesting when describing your power supply charger with current limiting. If I understood correctly, the current declined after a certain point and then leveled off at 50 ma. I think that suggests that if you wanted to maintain a given charge current, you would have to slowly increase the charge voltage as the battery charges.
It's possible you could benefit from the use of a Solar Battery Charger. Several are available on Amazon and they can operate on the dashboard or in a window. If you park outside in the sun it might be worth reading the reviews to see what you can learn.
Steve Wilson
Jul 15, 2017, 7:30:38 PM7/15/17
to
perhaps 100mA, then suddenly went into current limiting around 14.5
Volts. It stayed in current limit for only a few minutes, then gradually
tapered off in a linear fashion down to 50 mA. Ther threshold is very
sharp, perhaps 100 to 200mV.
This tells me the alternator voltage must be high enough to rise above
the battery threshold in order to charge the battery. A lower voltage,
even a couple of tenths of a volt, will do little to charge the battery.
Of course, the voltage changes with temperature. This is documented on a
number of sites, but I believe the change is around -2mV per degree F. So
on a hot day, + 30C, the threshold voltage will decrease, and on a cold
day, -20C, the required voltage will increase.
The car makers have wildly differing opinions on what the optimum voltage
should be. My neighour had a Pontiac Trans AM (I forget what year,
perhaps around 2006), and her alternator put out 15.5V after starting.
Definitely on the high side, but it didn't seem to harm the battery. The
battery was a GM side mount and the connection got corroded, so I was out
in -30C weather more than once to try and start her car. Fortunately, she
traded it in on a new Nissan and I have not been asked to start her car
since. Horay!
I got the bug to install a solar charger. There are a number of problems.
For example, the sun angle in winter is very low, so the solar array has
to be tilted to get much energy. However, the snow fall overnight can be
half a foot or more, which would cover the array. Trying to brush it off
might mean damaging the array, since it is hard to find under the snow. I
did order three arrays to try to capture as much energy as possible, but
only one arrived. The others were lost in shipment.
The other problem is trying to capture as much energy as possible, then
to transfer it to the battery. One approach is to charge a battery bank,
then start a SEPIC converter to charge the battery until the capacitor
bank decayed to some suitable voltage. I found that the local electronics
recycle bin often contains discarded high power stereo amplifiers, which
contain large value electrolytic capacitors. I had collected quite a few
of these before I traded the old Taurus for a new Ford Focus. The Focus
seems to be doing a bit better to charge the battery - a least it hasn't
failed to start even in winter. So I am monitoring the situation and as
long as the car continues to start, I see little reason to get excited.
However, now that the temperatures are starting to climb, I am getting a
little nervous. The alternator is starting to put out 14.2 to 14.3V,
which I believe is too low to charge the battery. Accordingly, the
unloaded battery voltage is starting to decrease. It was 12.2v this
morning. So I believe the battery is heading to an early death, which
could be prevented if the alternator put out a higher voltage.
Now I am looking at making a simple circuit to intercept the PWM commands
from the engine control, and inserting my own PWM command to the
alternator to tell it to keep the voltage at 14.5, regardless of
different loads such as air conditioning, headlights, and so on. Once the
battery has charged, the drain on the alternator drops to insignificant
levels, so the higher voltage should have little effect on the
alternator.
I remember the old days when cars used a generator with brushes, and the
regulator was some relays that you could adjust the voltage to whatever
you wished. The battery would last for 5 or 6 years with no problem, even
with the harsh winter. Now, the electronics have taken over, the the
algorithms don't seem to have been written by someone who understands
what they are doing. So I am interested in overriding their poor
performance. But it is very hard to find any information on the PWM
signals and how to insert a different command without upsetting the
engine control software.
Sorry for the long post. There was a lot of detail to cover.
pcdh...@gmail.com
Jul 15, 2017, 8:09:06 PM7/15/17
to
>As I brought up the voltage, the current rose from a very low level,
>perhaps 100mA, then suddenly went into current limiting around 14.5
>Volts. It stayed in current limit for only a few minutes, then gradually
>tapered off in a linear fashion down to 50 mA. Their threshold is very
>perhaps 100mA, then suddenly went into current limiting around 14.5
>Volts. It stayed in current limit for only a few minutes, then gradually
>sharp, perhaps 100 to 200mV.
>This tells me the alternator voltage must be high enough to rise above
>the battery threshold in order to charge the battery. A lower voltage,
>even a couple of tenths of a volt, will do little to charge the battery
IOW large lead-acid batteries have very low impedances, which is more or less the point. The open-circuit alternator voltage will be nearly proportional to rotor speed till iron and copper loss take over. That's why I suggested a smaller alternator pulley (upthread someplace.)
>This tells me the alternator voltage must be high enough to rise above
>the battery threshold in order to charge the battery. A lower voltage,
>even a couple of tenths of a volt, will do little to charge the battery
Cheers
Phil Hobbs
Steve Wilson
Jul 15, 2017, 8:21:00 PM7/15/17
to
large current when the car was idling.
However, since I started monitoring the alternator voltage, I found it
can easily reach 15V when the engine is idling. At this level, the
battery only takes current for a short time, then the drain drops off to
near zero.
So the issue is not so much getting enough voltage from the alternator,
but rather to intercept the PWM commands from the engine control and
insert commands that will tell the alternator to put out the correct
voltge to charge the battery.
Since modern engines start so quickly, there is not much energy taken
from the battery. It can be easily replaced, even on a short trip, if the
alternator voltage is set correctly. It appears that the Ford Taurus and
Focus, my neighbour's Trans AM, and the Camry and Honda fail to do so.
Jim Thompson
Jul 15, 2017, 9:02:29 PM7/15/17
to
required versus temperature.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I'm looking for work... see my website.
kt77
Jul 16, 2017, 1:40:14 PM7/16/17
to
On Saturday, July 15, 2017 at 4:30:38 PM UTC-7, Steve Wilson wrote:
> The alternator is starting to put out 14.2 to 14.3V,
> which I believe is too low to charge the battery. Accordingly, the
> unloaded battery voltage is starting to decrease. It was 12.2v this
> morning. So I believe the battery is heading to an early death, which
> could be prevented if the alternator put out a higher voltage.
That voltage range should be fine if the battery is in good condition and you drive reasonable length trips. Charging systems today are designed to maintain a battery but not necessarily do a full recharge which takes many hours. One exception might be driving several hundred miles. A sulfated battery is very difficult to charge because of higher internal resistance and surface charge will build up quickly and reduce the charge current.
> The alternator is starting to put out 14.2 to 14.3V,
> which I believe is too low to charge the battery. Accordingly, the
> unloaded battery voltage is starting to decrease. It was 12.2v this
> morning. So I believe the battery is heading to an early death, which
> could be prevented if the alternator put out a higher voltage.
I assume you have a conventional flooded lead acid battery. It might be best to put it on a good quality charger and see if you can restore the charge. I would also check the specific gravity of each cell for any variation.
When my battery needed a jump, I found that driving 20 miles still left the specific gravity bordering on empty. I connected a Black & Decker 2 amp charger/maintainer and the 2 amp charge terminated after about 20 hours but the specific gravity had only moved up a small amount. I left the charger/maintainer connected for several weeks and to my surprise the specific gravity slowly increased to 1.295 which is the upper limit. It was a very slow process all occurring as the battery maintainer float voltage rose from 13.51 volts initially to 13.68 volts at the end of the period.
Make sure you measure battery voltage at the battery posts. In regards to your power supply reading 14.5 volts, there could be significant voltage drop depending on wire size and length. Reading the voltage at the supply could show a higher voltage than what is actually seen at the battery posts. The state of charge would also be a factor and the voltage would be higher if the battery was close to full charge.
Steve Wilson
Jul 17, 2017, 6:11:25 AM7/17/17
to
last fall it was 12.4V, a while ago it was 12.3V, now it is 12.2V. The
battery will probably not last through the next winter.
The voltage drop in the car is negligible. The wiring diagram shows a 30A
fuse between the 12V cigarette lighter and the battery. The voltmeter has a
100k resistor at the input. The drain is I = E / R, = 12 / 1e5, = 0.00012
A.
The wiring and fuse have very low resistance. Say we allow 0.1 volt drop at
30 A. The resistance is R = E / I, = 0.1 / 30, = 3.33 e-3 Ohms.
With the current drain from my voltmeter, the drop is E = I * R, = 0.00012
* 3.33 e-3, = 4e-7 V, = 400 nanovolts. The least significant digit on my
voltmeter is 0.001 Volt. I cannot even see 400 nanovolts.
When chargin the battery, the power supply is connected to the battery with
short lengths of 16Ga wire. The supply shows the voltage during current
limiting. I never measured the voltage during this interval since it was so
short. However, when it came out of current limit and the current decayed,
the voltage quickly rose to 14.5V. So I take that as the voltage required
to charge the battery.
It is clear the alternators in these discussions do not meet the minimum
voltage required to charge the battery. At most, perhaps a few hundred mA
flow, which will not restore the charge on a short trip.
I can't change the battery chemistry, or the length of the trips. But I can
change the alternator output voltage. I am studying the schematics for the
Ford Focus, and it seems the interface is very simple. It uses open-
collector drivers for the command to the alternator and the feddback from
the alternator. The frequency appears to be 150 Hz. It looks like all I
have to do is cut the command line and insert my own signal, with the duty
cycle selecting the desired alternator voltage. A very simple
microprocessor can measure the battery voltage and change the duty cycle to
drive the alternator voltage to 14.5V, and increase or decrease the voltage
according to the ambient temperature.
I have high confidence this will work on the Ford Focus. I do not have
schematics for the Honda, Camry, or other cars, so I cannot tell how
difficult it would be to convert their systems to a controlled charging
voltage. However, car manufacturing is driven by cost, and other
manufacturers will probably use a very similar system.
kt77
Jul 17, 2017, 2:02:40 PM7/17/17
to
On Monday, July 17, 2017 at 3:11:25 AM UTC-7, Steve Wilson wrote:
> It is clear the alternators in these discussions do not meet the minimum
> voltage required to charge the battery.
It might be worth reconnecting your power supply to verify the charging threshold. If the wiring resistance was 0.05 ohms that would drop 0.25 volts at 5 amps. My battery at nearly full charge measured 14.24 volts with a 2 amp charge. The amateur radio site that I referenced earlier mentioned 14.2-14.5 volts to charge in a reasonable time.
> It is clear the alternators in these discussions do not meet the minimum
> voltage required to charge the battery.
The Battery University website has information on the temperature compensation which is apparently 3 mv per cell per degree centigrade. That would be 0.18 volts for a six cell battery for a change of 10 degrees C or 18 degrees F.
I just realized that the alternator will warm up much faster than the heavy battery so the voltage may actually be too low until the battery warms up to compensate. That may never happen on a short trip.
Here is something else that might be of interest. There is a thread online mentioning that the internal resistance of a car battery is in the area of 0.02 ohms. That would drop the voltage 2 volts during a 100 amp load test. It would also mean that the charging voltage would need to rise an extra 0.2 volts under a 10 amp charge.
I actually calculated the same value earlier. My high beam headlights draw 10 amps. I turned on the headlights until the voltage stabilized and then turned on the high beams. The additional voltage drop was about 0.2 volts. Using ohms law the series resistance would be 0.2/10 = 0.02 ohms.
My previous car was a 2000 Camry. A Sears Diehard battery installed in 2005 lasted 8 years which was quite a surprise. The battery still started the engine but the specific gravity of one cell indicated half charge. I now wish I had measured the alternator voltage under different conditions. It's not hard to guess that the voltage regulator specifications differed from those of current models.
I think my battery was slowly discharged over time as a result of infrequent use, short trips, and parasitic current drain. The surprise is that the battery maintainer appears to have restored the battery to almost new condition.
Steve Wilson
Jul 17, 2017, 2:36:02 PM7/17/17
to
voltage drop is negligible. Say the resistance is 0.02 ohms. The voltage drop
is then E = I * R = 50e-3 * 0.02 = 0.001 Volt, or 1 millivolt. That is the
least significant digit on my voltmeter.
I think the problem is not so much measuring the battery voltage as much as
convincing the alternator to ignore the commands from the PCM and set the
charging voltage to 14.5V. Then the battery will be fully charged, even on
short trips.
This voltage is mentioned in numerous places. But none of the cars deliver
it.
kt77
Jul 17, 2017, 5:30:50 PM7/17/17
to
On Monday, July 17, 2017 at 11:36:02 AM UTC-7, Steve Wilson wrote:
>14.5V
It looks like fuel economy standards have really impacted voltage regulator specifications to reduce alternator load. I also would benefit if the charging system in my car was smart enough to properly charge the battery under all conditions.
I think 14.2 volts would still be adequate if it stayed at that level somewhat longer. The charge current should be a few amperes under those conditions and probably higher for a partially discharged battery. The voltage would need to be under 14.2 volts at higher temperatures.
My thought on your power supply would be to adjust the voltage to 15 volts and let the current limit take over. In that case you should have a constant current 5 amp charge. The voltage at the battery posts would rise as the battery charged but you could still measure the approximate threshold where the battery allowed a charge current of several amperes. The increase in voltage should be very gradual as it can take a long time to fully charge a battery. If you did this starting from 12.2 volts, I believe the voltage would rise fairly quickly as surface charge builds up on the plates. You could then see where the voltage leveled off before rising on a more gradual basis.
>14.5V
It looks like fuel economy standards have really impacted voltage regulator specifications to reduce alternator load. I also would benefit if the charging system in my car was smart enough to properly charge the battery under all conditions.
I think 14.2 volts would still be adequate if it stayed at that level somewhat longer. The charge current should be a few amperes under those conditions and probably higher for a partially discharged battery. The voltage would need to be under 14.2 volts at higher temperatures.
My thought on your power supply would be to adjust the voltage to 15 volts and let the current limit take over. In that case you should have a constant current 5 amp charge. The voltage at the battery posts would rise as the battery charged but you could still measure the approximate threshold where the battery allowed a charge current of several amperes. The increase in voltage should be very gradual as it can take a long time to fully charge a battery. If you did this starting from 12.2 volts, I believe the voltage would rise fairly quickly as surface charge builds up on the plates. You could then see where the voltage leveled off before rising on a more gradual basis.
Steve Wilson
Jul 17, 2017, 10:55:08 PM7/17/17
to
kt77 <kawi...@gmail.com> wrote:
> On Monday, July 17, 2017 at 11:36:02 AM UTC-7, Steve Wilson wrote:
>>14.5V
> It looks like fuel economy standards have really impacted voltage
> regulator specifications to reduce alternator load. I also would
> benefit if the charging system in my car was smart enough to properly
> charge the battery under all conditions.
I doubt fuel economy has much to do with it. Modern cars start so quickly
> On Monday, July 17, 2017 at 11:36:02 AM UTC-7, Steve Wilson wrote:
>>14.5V
> It looks like fuel economy standards have really impacted voltage
> regulator specifications to reduce alternator load. I also would
> benefit if the charging system in my car was smart enough to properly
> charge the battery under all conditions.
that little energy is drawn from the battery. At 14.5V, the energy is
replaced in a few minutes, then the battery drain drops to negligible
level. Where you get the huge drain is heated seats, rear window defrost,
high power audio systems, and all the various electronic gadgets that add
to the alternator drain. Charging the battery is completely negligible, if
the car manufacturers would settle on the correct voltage.
> I think 14.2 volts would still be adequate if it stayed at that level
> somewhat longer. The charge current should be a few amperes under those
> conditions and probably higher for a partially discharged battery. The
> voltage would need to be under 14.2 volts at higher temperatures.
14.5V.
> My thought on your power supply would be to adjust the voltage to 15
> volts and let the current limit take over. In that case you should have
> a constant current 5 amp charge. The voltage at the battery posts would
> rise as the battery charged but you could still measure the approximate
> threshold where the battery allowed a charge current of several amperes.
> The increase in voltage should be very gradual as it can take a long
> time to fully charge a battery. If you did this starting from 12.2
> volts, I believe the voltage would rise fairly quickly as surface charge
> builds up on the plates. You could then see where the voltage leveled
> off before rising on a more gradual basis.
times, I found it did exactly the same thing every time so I went to
straight 14.5V and let it go into current limiting. The whole charge cycle
only lasted a few minutes, then the battery drain rapidly dropped to 50mA
or so and stayed there. The same thing would happen in a car.
Again, many sites recommend 14.5V to charge the battery.
Just for infomation, here is the lab power supply I used:
http://cgi.ebay.com/272724909909
I bought three on the recommendation of another poster on this newsgroup.
It turns out to be very poor for electronics work. There is a huge
capacitor on the output. This will blow LEDs and ICs if you rely on current
limiting to save the device. In addition, there is a large overshoot on
power on, which could blow sensitive devices like laser diodes. I
definitely do not recommend this unit for lab work, but it is OK for
charging batteries. But I bought too many and paid too much.
Michael A. Terrell
Jul 18, 2017, 2:48:46 AM7/18/17
to
Steve Wilson wrote:
>
> I did walk the current up at the beginning, but after a half-dozen or > so times, I found it did exactly the same thing every time so I went > to straight 14.5V and let it go into current limiting. The whole
> charge cycle only lasted a few minutes, then the battery drain
> rapidly dropped to 50mA or so and stayed there. The same thing would > happen in a car.
>
> Again, many sites recommend 14.5V to charge the battery.
>
> Just for information, here is the lab power supply I used:
>
> I did walk the current up at the beginning, but after a half-dozen or > so times, I found it did exactly the same thing every time so I went > to straight 14.5V and let it go into current limiting. The whole
> charge cycle only lasted a few minutes, then the battery drain
> rapidly dropped to 50mA or so and stayed there. The same thing would > happen in a car.
>
> Again, many sites recommend 14.5V to charge the battery.
>
>
> http://cgi.ebay.com/272724909909
>
> I bought three on the recommendation of another poster on this newsgroup.
>
> It turns out to be very poor for electronics work. There is a huge
> capacitor on the output. This will blow LEDs and ICs if you rely on
> current limiting to save the device. In addition, there is a large
> overshoot on power on, which could blow sensitive devices like laser > diodes. I definitely do not recommend this unit for lab work, but it > is OK for charging batteries. But I bought too many and paid too much.
I bought an Instek (Goodwill Industries) GPS1850D version for $17,
> http://cgi.ebay.com/272724909909
>
> I bought three on the recommendation of another poster on this newsgroup.
>
> It turns out to be very poor for electronics work. There is a huge
> capacitor on the output. This will blow LEDs and ICs if you rely on
> current limiting to save the device. In addition, there is a large
> overshoot on power on, which could blow sensitive devices like laser > diodes. I definitely do not recommend this unit for lab work, but it > is OK for charging batteries. But I bought too many and paid too much.
but I prefer the 50 year old HP power supplies that I buy 'not
working/for parts only' and rebuild. Some are so large that they need a
decent relay rack to handle their weight. :)
--
Never piss off an Engineer!
They don't get mad.
They don't get even.
They go for over unity! ;-)
Spehro Pefhany
Jul 18, 2017, 7:30:12 AM7/18/17
to
On Tue, 18 Jul 2017 02:55:02 GMT, the renowned Steve Wilson
<n...@spam.com> wrote:
>
>I doubt fuel economy has much to do with it. Modern cars start so quickly
>that little energy is drawn from the battery. At 14.5V, the energy is
>replaced in a few minutes, then the battery drain drops to negligible
>level. Where you get the huge drain is heated seats, rear window defrost,
>high power audio systems, and all the various electronic gadgets that add
>to the alternator drain. Charging the battery is completely negligible, if
>the car manufacturers would settle on the correct voltage.
Not just gadgets, many cars have electric power steering, electric
<n...@spam.com> wrote:
>
>I doubt fuel economy has much to do with it. Modern cars start so quickly
>that little energy is drawn from the battery. At 14.5V, the energy is
>replaced in a few minutes, then the battery drain drops to negligible
>level. Where you get the huge drain is heated seats, rear window defrost,
>high power audio systems, and all the various electronic gadgets that add
>to the alternator drain. Charging the battery is completely negligible, if
>the car manufacturers would settle on the correct voltage.
water pumps etc.
--sp
--
Best regards,
Spehro Pefhany
Steve Wilson
Jul 18, 2017, 8:31:47 AM7/18/17
to
Spehro Pefhany <spef...@interlogDOTyou.knowwhat> wrote:
> Not just gadgets, many cars have electric power steering, electric
> water pumps etc.
> --sp
Thanks. I didn't know that. It sounds silly. To go from a pully on a power
> Not just gadgets, many cars have electric power steering, electric
> water pumps etc.
> --sp
steering pump, to a pully on the alternator, then to an electric motor to
drive the power steering pump or water pump, seems like a huge waste of
energy. It has to affect gas mileage.
Steve Wilson
Jul 18, 2017, 11:46:02 AM7/18/17
to
the switch to electric motors.
1. Power Steering
Electric power steering has some significant advantages over any form of
conventional hydraulic steering, both for the owner of the car and its
manufacturer. The reduction in engine load of an electric power steering
system (it can be as low as 4 watts when the car is being driven in a
straight line) means that the fuel economy of a car equipped with electric
power steering is very similar to that of a car with no form of power
steering. Analyses provided by manufacturers of electric power steering
systems indicate potential fuel savings of 4-8 per cent over cars equipped
with conventional hydraulic steering, with the lighter mass of an electric
power steering also having an impact here. The independence of the system
from engine operation also means that should the engine stall, steering
assistance does not change.
http://www.autospeed.com/cms/article.html?&title=Electric-Power-Steering&A=
110661
2. Not all agree it's better
Electrically assisted power steering (EPS) is the latest technological
cross we bear. Replacing hydraulic assist with a computer-controlled
electric motor seemed like a reasonable idea when it first surfaced.
Someday every car control will be by-wire; today’s EPS looks like a step
in that direction. But in the past decade of driving EPS-equipped cars,
we’ve found them lacking in feel, poorly tuned, and sometimes simply weird
in comparison with the hydraulic-assist setups that have benefited from
more than half a century of development.
http://www.caranddriver.com/features/electric-vs-hydraulic-steering-a-compr
ehensive-comparison-test-feature
3. Water Pump
According to Davies Craig, an electric water pump has a number of
advantages over the engine-driven variety. They point out an EWP will
increase power sent to the drive wheels because the power the mechanical
pump takes from the engine increases dramatically with its speed—when the
pump speed doubles from idle, say 600 rpm to 1,200 rpm, the power it takes
increases by eight times, then eight times going to 2,400 rpm and so on.
This extra power and torque released by disabling the mechanical pump now
goes to the drive wheels. Additional benefits of an electric pump are
improved cooling capacity and fuel economy along with the elimination of
engine heat soak after a hot shut down. Engine cooling is improved with an
EWP thanks to a higher flow rate at idle and low engine speeds when there
is little or no ram air, and when the engine is switched off.
http://www.hotrod.com/articles/davies-craig-reinvents-the-electric-water-pu
mp/
These arguments make good sense. Thanks.
kevin93
Jul 18, 2017, 1:58:03 PM7/18/17
to
On Saturday, July 15, 2017 at 5:09:06 PM UTC-7, pcdh...@gmail.com wrote:
...
At that speed the open circuit voltage will probably be in the 100-150v range - it is even possible to get 120V AC from a car alternator by modifying the regulator. At idle speed there should still be enough to provide power to the 12v system.
The output impedance of the alternator is highly inductive and since the impedance rises proportional to frequency the current is somewhat independent of engine speed. Most alternators do not have any specific current limiting - they just rely on this inductance.
kevin
...
> IOW large lead-acid batteries have very low impedances, which is more or less the point. The open-circuit alternator voltage will be nearly proportional to rotor speed till iron and copper loss take over. That's why I suggested a smaller alternator pulley (upthread someplace.)
>
> Cheers
>
> Phil Hobbs
The pulley size on car alternators is usually selected to give a maximum alternator speed of abut 12,500 RPM at the maximum engine speed - beyond that speed the slip-ring contact, bearings and structural strength of the rotor etc start to have problems.
>
> Cheers
>
> Phil Hobbs
At that speed the open circuit voltage will probably be in the 100-150v range - it is even possible to get 120V AC from a car alternator by modifying the regulator. At idle speed there should still be enough to provide power to the 12v system.
The output impedance of the alternator is highly inductive and since the impedance rises proportional to frequency the current is somewhat independent of engine speed. Most alternators do not have any specific current limiting - they just rely on this inductance.
kevin
kt77
Jul 18, 2017, 2:34:52 PM7/18/17
to
Take a look at the first paragraph in this detailed description of the Honda Dual-Mode Charging System. The CAFE standards have resulted in charging systems doing what they can to minimize alternator load.
http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto_pres
Yesterday I recharged my battery and wrote down some very interesting data. I feel much better about my voltage regulator settings at least for the initial part of the charge. My battery was discharged enough for my 2 amp charger to run for 55 minutes. The battery started at a voltage of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked the voltage at the battery posts and watched the voltage rise all the way from 12.93 volts to 14.26 volts. The rise was fairly steep initially taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts. The rise then became more gradual with the voltage rising to 14.26 volts after 55 minutes.
If an alternator had been doing the charging at a relatively constant voltage, the charge current would have been quite high initially followed by a gradual decline. Consider the factors that determine charge current.
A simple model for a lead-acid battery would be a variable ideal voltage source in series with a variable series resistance. It's easy to see that charging current could be calculated using Ohm's Law. The three variables would be alternator voltage, battery voltage, and the series resistance. Current will flow whenever the alternator voltage is just slightly higher than the battery voltage which may include surface charge.
The remaining issue is what happens after surface charge builds up. It is probably not a problem if the battery is near full charge. However, if a battery is at 50% charge, it takes time and amperage to restore the charge. The voltage regulator settings might be more important for this case to achieve the required charging current. Short trips would be an additional concern.
http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto_pres
Yesterday I recharged my battery and wrote down some very interesting data. I feel much better about my voltage regulator settings at least for the initial part of the charge. My battery was discharged enough for my 2 amp charger to run for 55 minutes. The battery started at a voltage of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked the voltage at the battery posts and watched the voltage rise all the way from 12.93 volts to 14.26 volts. The rise was fairly steep initially taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts. The rise then became more gradual with the voltage rising to 14.26 volts after 55 minutes.
If an alternator had been doing the charging at a relatively constant voltage, the charge current would have been quite high initially followed by a gradual decline. Consider the factors that determine charge current.
A simple model for a lead-acid battery would be a variable ideal voltage source in series with a variable series resistance. It's easy to see that charging current could be calculated using Ohm's Law. The three variables would be alternator voltage, battery voltage, and the series resistance. Current will flow whenever the alternator voltage is just slightly higher than the battery voltage which may include surface charge.
The remaining issue is what happens after surface charge builds up. It is probably not a problem if the battery is near full charge. However, if a battery is at 50% charge, it takes time and amperage to restore the charge. The voltage regulator settings might be more important for this case to achieve the required charging current. Short trips would be an additional concern.
Steve Wilson
Jul 18, 2017, 5:19:33 PM7/18/17
to
kt77 <kawi...@gmail.com> wrote:
> Take a look at the first paragraph in this detailed description of the
> Honda Dual-Mode Charging System. The CAFE standards have resulted in
> charging systems doing what they can to minimize alternator load.
>
> http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto
> _pres
>
> Yesterday I recharged my battery and wrote down some very interesting
> data. I feel much better about my voltage regulator settings at least
> for the initial part of the charge. My battery was discharged enough for
> my 2 amp charger to run for 55 minutes. The battery started at a voltage
> of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked
> the voltage at the battery posts and watched the voltage rise all the
> way from 12.93 volts to 14.26 volts. The rise was fairly steep initially
> taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts.
> The rise then became more gradual with the voltage rising to 14.26 volts
> after 55 minutes.
You still never made it to 14.5V
> Take a look at the first paragraph in this detailed description of the
> Honda Dual-Mode Charging System. The CAFE standards have resulted in
> charging systems doing what they can to minimize alternator load.
>
> http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto
> _pres
>
> Yesterday I recharged my battery and wrote down some very interesting
> data. I feel much better about my voltage regulator settings at least
> for the initial part of the charge. My battery was discharged enough for
> my 2 amp charger to run for 55 minutes. The battery started at a voltage
> of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked
> the voltage at the battery posts and watched the voltage rise all the
> way from 12.93 volts to 14.26 volts. The rise was fairly steep initially
> taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts.
> The rise then became more gradual with the voltage rising to 14.26 volts
> after 55 minutes.
> If an alternator had been doing the charging at a relatively constant
> voltage, the charge current would have been quite high initially
> followed by a gradual decline. Consider the factors that determine
> charge current.
> A simple model for a lead-acid battery would be a variable ideal voltage
> source in series with a variable series resistance. It's easy to see
> that charging current could be calculated using Ohm's Law. The three
> variables would be alternator voltage, battery voltage, and the series
> resistance. Current will flow whenever the alternator voltage is just
> slightly higher than the battery voltage which may include surface
> charge.
> The remaining issue is what happens after surface charge builds up. It
> is probably not a problem if the battery is near full charge. However,
> if a battery is at 50% charge, it takes time and amperage to restore the
> charge. The voltage regulator settings might be more important for this
> case to achieve the required charging current. Short trips would be an
> additional concern.
Steve Wilson
Jul 18, 2017, 5:25:07 PM7/18/17
to
Sorry if this is a dupe. Newsgroup did something wierd on the first try.
kt77 <kawi...@gmail.com> wrote:
> Take a look at the first paragraph in this detailed description of the
> Honda Dual-Mode Charging System. The CAFE standards have resulted in
> charging systems doing what they can to minimize alternator load.
>
> http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto
> _pres
> Yesterday I recharged my battery and wrote down some very interesting
> data. I feel much better about my voltage regulator settings at least
> for the initial part of the charge. My battery was discharged enough for
> my 2 amp charger to run for 55 minutes. The battery started at a voltage
> of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked
> the voltage at the battery posts and watched the voltage rise all the
> way from 12.93 volts to 14.26 volts. The rise was fairly steep initially
> taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts.
> The rise then became more gradual with the voltage rising to 14.26 volts
> after 55 minutes.
You never made it to 14.5V
> If an alternator had been doing the charging at a relatively constant
> voltage, the charge current would have been quite high initially
> followed by a gradual decline. Consider the factors that determine
> charge current.
> A simple model for a lead-acid battery would be a variable ideal voltage
> source in series with a variable series resistance. It's easy to see
> that charging current could be calculated using Ohm's Law. The three
> variables would be alternator voltage, battery voltage, and the series
> resistance. Current will flow whenever the alternator voltage is just
> slightly higher than the battery voltage which may include surface
> charge.
LTspice uses a large capacitor as a model for a battery.
> The remaining issue is what happens after surface charge builds up. It
> is probably not a problem if the battery is near full charge. However,
> if a battery is at 50% charge, it takes time and amperage to restore the
> charge. The voltage regulator settings might be more important for this
> case to achieve the required charging current. Short trips would be an
> additional concern.
You may need to put your battery on charge after every trip.
kt77 <kawi...@gmail.com> wrote:
> Take a look at the first paragraph in this detailed description of the
> Honda Dual-Mode Charging System. The CAFE standards have resulted in
> charging systems doing what they can to minimize alternator load.
>
> http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto
> _pres
> Yesterday I recharged my battery and wrote down some very interesting
> data. I feel much better about my voltage regulator settings at least
> for the initial part of the charge. My battery was discharged enough for
> my 2 amp charger to run for 55 minutes. The battery started at a voltage
> of 12.75 volts and charged at 2 amps for the full 55 minutes. I checked
> the voltage at the battery posts and watched the voltage rise all the
> way from 12.93 volts to 14.26 volts. The rise was fairly steep initially
> taking 1 minute to reach 13.27 volts and 8 minutes to reach 14 volts.
> The rise then became more gradual with the voltage rising to 14.26 volts
> after 55 minutes.
> If an alternator had been doing the charging at a relatively constant
> voltage, the charge current would have been quite high initially
> followed by a gradual decline. Consider the factors that determine
> charge current.
> A simple model for a lead-acid battery would be a variable ideal voltage
> source in series with a variable series resistance. It's easy to see
> that charging current could be calculated using Ohm's Law. The three
> variables would be alternator voltage, battery voltage, and the series
> resistance. Current will flow whenever the alternator voltage is just
> slightly higher than the battery voltage which may include surface
> charge.
> The remaining issue is what happens after surface charge builds up. It
> is probably not a problem if the battery is near full charge. However,
> if a battery is at 50% charge, it takes time and amperage to restore the
> charge. The voltage regulator settings might be more important for this
> case to achieve the required charging current. Short trips would be an
> additional concern.
Spehro Pefhany
Jul 18, 2017, 6:48:22 PM7/18/17
to
On Tue, 18 Jul 2017 15:45:54 GMT, the renowned Steve Wilson
<n...@spam.com> wrote:
>
>
>These arguments make good sense. Thanks.
Nice answers. I think another factor is that the accessories can run
<n...@spam.com> wrote:
>
>
>These arguments make good sense. Thanks.
for brief periods from the battery so more of the HP from the engine
is available to drive the wheels when passing or going up a steep
hill, thus allowing a smaller displacement IC engine to give the same
performance as a larger one (which also reduces fuel consumption).
The servo steering can easily be made speed sensitive, which improves
the driving experience.
Lasse Langwadt Christensen
Jul 18, 2017, 7:13:36 PM7/18/17
to
Steve Wilson
Jul 18, 2017, 7:22:52 PM7/18/17
to
you have ever lost the engine in a high speed curve on the side of a
mountain, you may agree there is probably little that is so frightening.
Peabody
Jul 18, 2017, 9:12:06 PM7/18/17
to
Steve Wilson says...
> I think the problem is not so much measuring the battery
> voltage as much as convincing the alternator to ignore
> the commands from the PCM and set the charging voltage
> to 14.5V. Then the battery will be fully charged, even
> on short trips.
My Honda keeps the alternator at 14.4V so long as the
headlights are on. That shouldn't be necessary, but seems
to work.
> I think the problem is not so much measuring the battery
> voltage as much as convincing the alternator to ignore
> the commands from the PCM and set the charging voltage
> to 14.5V. Then the battery will be fully charged, even
> on short trips.
headlights are on. That shouldn't be necessary, but seems
to work.
Jim Thompson
Jul 18, 2017, 9:51:06 PM7/18/17
to
voltage AT the battery, use a proper TC (measure temperature AT
battery)... trivial to do.
Lasse Langwadt Christensen
Jul 18, 2017, 10:07:20 PM7/18/17
to
Den onsdag den 19. juli 2017 kl. 03.51.06 UTC+2 skrev Jim Thompson:
> On Tue, 18 Jul 2017 20:11:57 -0500, Peabody
> <waybackNO...@yahoo.com> wrote:
>
> >Steve Wilson says...
> >
> > > I think the problem is not so much measuring the battery
> > > voltage as much as convincing the alternator to ignore
> > > the commands from the PCM and set the charging voltage
> > > to 14.5V. Then the battery will be fully charged, even
> > > on short trips.
> >
> >My Honda keeps the alternator at 14.4V so long as the
> >headlights are on. That shouldn't be necessary, but seems
> >to work.
>
> This is a design group... roll your own regulator already... sense the
> voltage AT the battery, use a proper TC (measure temperature AT
> battery)... trivial to do.
unless of course result is that the ECU tells you that something is wrong
> On Tue, 18 Jul 2017 20:11:57 -0500, Peabody
> <waybackNO...@yahoo.com> wrote:
>
> >Steve Wilson says...
> >
> > > I think the problem is not so much measuring the battery
> > > voltage as much as convincing the alternator to ignore
> > > the commands from the PCM and set the charging voltage
> > > to 14.5V. Then the battery will be fully charged, even
> > > on short trips.
> >
> >My Honda keeps the alternator at 14.4V so long as the
> >headlights are on. That shouldn't be necessary, but seems
> >to work.
>
> This is a design group... roll your own regulator already... sense the
> voltage AT the battery, use a proper TC (measure temperature AT
> battery)... trivial to do.
with the charging and you to get to service
Jim Thompson
Jul 18, 2017, 10:24:25 PM7/18/17
to
Steve Wilson
Jul 18, 2017, 10:29:34 PM7/18/17
to
Maybe the battery contacts have corroded. Have you cleaned them with a wire
brush? I found that a thin coating of vaseline helps improve the connection
and reduce corrosion from the sulphuric acid.
Lasse Langwadt Christensen
Jul 18, 2017, 10:52:32 PM7/18/17
to
Den onsdag den 19. juli 2017 kl. 04.24.25 UTC+2 skrev Jim Thompson:
> On Tue, 18 Jul 2017 19:07:14 -0700 (PDT), Lasse Langwadt Christensen
> <lang...@fonz.dk> wrote:
>
> >Den onsdag den 19. juli 2017 kl. 03.51.06 UTC+2 skrev Jim Thompson:
> >> On Tue, 18 Jul 2017 20:11:57 -0500, Peabody
> >> <waybackNO...@yahoo.com> wrote:
> >>
> >> >Steve Wilson says...
> >> >
> >> > > I think the problem is not so much measuring the battery
> >> > > voltage as much as convincing the alternator to ignore
> >> > > the commands from the PCM and set the charging voltage
> >> > > to 14.5V. Then the battery will be fully charged, even
> >> > > on short trips.
> >> >
> >> >My Honda keeps the alternator at 14.4V so long as the
> >> >headlights are on. That shouldn't be necessary, but seems
> >> >to work.
> >>
> >> This is a design group... roll your own regulator already... sense the
> >> voltage AT the battery, use a proper TC (measure temperature AT
> >> battery)... trivial to do.
> >
> >unless of course result is that the ECU tells you that something is wrong
> >with the charging and you to get to service
>
> Unless you know what you are doing ;-)
it is not the 80's
> On Tue, 18 Jul 2017 19:07:14 -0700 (PDT), Lasse Langwadt Christensen
> <lang...@fonz.dk> wrote:
>
> >Den onsdag den 19. juli 2017 kl. 03.51.06 UTC+2 skrev Jim Thompson:
> >> On Tue, 18 Jul 2017 20:11:57 -0500, Peabody
> >> <waybackNO...@yahoo.com> wrote:
> >>
> >> >Steve Wilson says...
> >> >
> >> > > I think the problem is not so much measuring the battery
> >> > > voltage as much as convincing the alternator to ignore
> >> > > the commands from the PCM and set the charging voltage
> >> > > to 14.5V. Then the battery will be fully charged, even
> >> > > on short trips.
> >> >
> >> >My Honda keeps the alternator at 14.4V so long as the
> >> >headlights are on. That shouldn't be necessary, but seems
> >> >to work.
> >>
> >> This is a design group... roll your own regulator already... sense the
> >> voltage AT the battery, use a proper TC (measure temperature AT
> >> battery)... trivial to do.
> >
> >unless of course result is that the ECU tells you that something is wrong
> >with the charging and you to get to service
>
> Unless you know what you are doing ;-)
kevin93
Jul 18, 2017, 10:54:19 PM7/18/17
to
On Tuesday, July 18, 2017 at 7:29:34 PM UTC-7, Steve Wilson wrote:
..
There is also a "Battery Sulfation" mode where it regulates the voltage between 13.9 and 15.5 for about 5 minutes if the battery has been below 13.2v for 30 minutes.
Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so its a compromise.
This page on Battery University describes the situation (http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery) . For maximum battery life around 13.8v to 14.4 is recommended.
kevin
..
> > My Honda keeps the alternator at 14.4V so long as the
> > headlights are on. That shouldn't be necessary, but seems
> > to work.
>
> That is wierd. What is the voltage with the headlights off?
>
> Maybe the battery contacts have corroded. Have you cleaned them with a wire
> brush? I found that a thin coating of vaseline helps improve the connection
> and reduce corrosion from the sulphuric acid.
I have a GM service manual describing the charging protocol and "Headlight mode" is one of the 6 voltage regulation modes where it will be regulated between 13.9 and 14.5v depending upon temperature.
> > headlights are on. That shouldn't be necessary, but seems
> > to work.
>
> That is wierd. What is the voltage with the headlights off?
>
> Maybe the battery contacts have corroded. Have you cleaned them with a wire
> brush? I found that a thin coating of vaseline helps improve the connection
> and reduce corrosion from the sulphuric acid.
There is also a "Battery Sulfation" mode where it regulates the voltage between 13.9 and 15.5 for about 5 minutes if the battery has been below 13.2v for 30 minutes.
Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so its a compromise.
This page on Battery University describes the situation (http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery) . For maximum battery life around 13.8v to 14.4 is recommended.
kevin
kt77
Jul 18, 2017, 11:00:38 PM7/18/17
to
On Tuesday, July 18, 2017 at 2:19:33 PM UTC-7, Steve Wilson wrote:
> You still never made it to 14.5V
> You still never made it to 14.5V
> It looks like you need to put your battery on charge after every trip.
The Black & Decker 2 amp battery charger/maintainer detected full charge and switched to maintain mode. The voltage read 14.26 volts at that point. That voltage is consistent with the 14.2-14.5 volt range mentioned on the W8JI website that I referenced earlier.
I think the car will be fine if driven several times per week. As you may recall, the battery read 12.85 volts last week the morning after driving the car.
In thinking about the power supply test you mentioned, the narrow 0.1-0.2 volt band where the current increased sharply will likely vary quite a bit depending on the state of the battery.
If you repeated that test with your current battery at 12.2 volts, the band would be in the low 12 volt region initially and then rise as surface charge builds up. If you had a fully charged battery plus a full surface charge, the band would likely be in the low to mid 14 volt range.
Jim Thompson
Jul 19, 2017, 12:18:17 AM7/19/17
to
On Tue, 18 Jul 2017 19:52:23 -0700 (PDT), Lasse Langwadt Christensen
I see you have no experience tricking an ECU ?;-)
Michael A. Terrell
Jul 19, 2017, 2:03:05 AM7/19/17
to
Steve Wilson wrote:
>
> I really like the idea of not losing power steering if the engine
> quits. If you have ever lost the engine in a high speed curve on the > side of a mountain, you may agree there is probably little that is so > frightening.
Then you should never try having the hood latch ripping loose from
>
> I really like the idea of not losing power steering if the engine
> quits. If you have ever lost the engine in a high speed curve on the > side of a mountain, you may agree there is probably little that is so > frightening.
the body, the left hinge pulling loose, the hood smashing the reservoir
on the master cylinder, and damaging the carburetor so you can't slow
down in afternoon rush hour traffic on I-75 in Cincinnati.
The hood twisted 180 degrees, and caught on the wiper post, so I
couldn't see, I had no brakes, and the engine was running wide open.
The shuttle bus I used to ride from Ft. Greeley to Fairbanks back in
the '70s went over the side of the mountain, a few weeks after I got out
of the Army. Friends of mine were on it. The ended up in the hospital,
but only because it was caught in some trees, rather than falling all
the way to the ground.
Steve Wilson
Jul 19, 2017, 1:33:35 PM7/19/17
to
kt77 <kawi...@gmail.com> wrote:
> On Tuesday, July 18, 2017 at 2:19:33 PM UTC-7, Steve Wilson wrote:
>> You still never made it to 14.5V
>> It looks like you need to put your battery on charge after every trip.
> The Black & Decker 2 amp battery charger/maintainer detected full charge
> and switched to maintain mode. The voltage read 14.26 volts at that
> point. That voltage is consistent with the 14.2-14.5 volt range
> mentioned on the W8JI website that I referenced earlier.
Your method charging will put charge into the battery. However, it does not
> On Tuesday, July 18, 2017 at 2:19:33 PM UTC-7, Steve Wilson wrote:
>> You still never made it to 14.5V
>> It looks like you need to put your battery on charge after every trip.
> The Black & Decker 2 amp battery charger/maintainer detected full charge
> and switched to maintain mode. The voltage read 14.26 volts at that
> point. That voltage is consistent with the 14.2-14.5 volt range
> mentioned on the W8JI website that I referenced earlier.
fully charge the battery, which means you won't get the performance and
long life it could have.
The only way to fully charge the battery is to use saturation charging.
This charges at a constant current until the set voltage is reached, when
it switches to constant voltage mode. The current then decays to almost
zero. The charger is a cccv, for constnt current, constant voltage, and is
the kind I use. My set point is 14.5V. As I have mentioned before, just a
few tenths of a volt less that 14.5V means very little current flows into
the battery and it will not do saturation charging.
You can read about it in the Battery University article, "BU-403: Charging
Lead Acid", at
http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery
See figure 1.
There are a number of other articles on lead acid batteries listed that you
may wish to read.
kt77
Jul 20, 2017, 3:42:21 PM7/20/17
to
On Wednesday, July 19, 2017 at 10:33:35 AM UTC-7, Steve Wilson wrote:
> You can read about it in the Battery University article, "BU-403: Charging
> Lead Acid".
> You can read about it in the Battery University article, "BU-403: Charging
Thanks for the information on constant current, constant voltage and float charging. The section that really interested me was the discussion on the choice of cell voltage.
The range 2.30-2.35 volts per cell (13.8-14.1 volts) indicated maximum service life. The range 2.40-2.45 volts per cell (14.4-14.7 volts) offered higher capacity and less sulfation but problems with temperature and the need to add water.
This suggests that 13.8-14.1 volts should still charge the battery more than adequately and result in longer service life.
The other issue is that the car alternator does not charge with constant current followed by constant voltage. In addition, it's not clear if a given charging system switches to the proper float voltage if the battery becomes fully charged.
I connected my Black & Decker 2 amp charger/maintainer recently in part because the car had not been driven. It looks as though my battery loses about 3 Amp-Hours per week to parasitic current and self discharge. In reality, I should be able to go quite a long time if starting with a fully charged battery.
Even though the charger/maintainer may not be doing the three phase saturation charge described on the website, the specific gravity has risen to 1.295 which is actually above the thresholds normally mentioned for full charge. I've heard that a lead-acid battery can still be fully charged at lower current but it will take longer.
Steve Wilson
Jul 20, 2017, 6:19:21 PM7/20/17
to
kt77 <kawi...@gmail.com> wrote:
> On Wednesday, July 19, 2017 at 10:33:35 AM UTC-7, Steve Wilson wrote:
>> You can read about it in the Battery University article, "BU-403:
>> Chargin g Lead Acid".
> On Wednesday, July 19, 2017 at 10:33:35 AM UTC-7, Steve Wilson wrote:
>> You can read about it in the Battery University article, "BU-403:
> Thanks for the information on constant current, constant voltage and
> float charging. The section that really interested me was the discussion
> on the choice of cell voltage.
> The range 2.30-2.35 volts per cell (13.8-14.1 volts) indicated maximum
> service life. The range 2.40-2.45 volts per cell (14.4-14.7 volts)
> offered higher capacity and less sulfation but problems with temperature
> and the need to add water.
then switch to constant voltage. The current will decay to near zero.
This means very little temperature increase. For example, P = E * I = 14.5
* 0.05 = 0.725 Watt. That is negligible.
When the curent is near zero, there is very little gassing and no need to
add water. I checked the water level in the battery fairly often and never
needed to add water. So there was little or no gassing.
However, at lower voltages there is the risk of sulfation. This can destroy
the battery's ability to accept a charge.
> This suggests that 13.8-14.1 volts should still charge the battery more
> than adequately and result in longer service life.
cost $450, plus $500 to change the alternator. The new alternator did the
same thing as the old one.
> The other issue is that the car alternator does not charge with constant
> current followed by constant voltage. In addition, it's not clear if a
> given charging system switches to the proper float voltage if the
> battery becomes fully charged.
reach full charge and the current will drop to near zero. This means you
can keep the battery at full charge even on short trips.
I never bothered with changing the voltage to float voltage. Since the
current was already near zero, there was little point.
> I connected my Black & Decker 2 amp charger/maintainer recently in part
> because the car had not been driven. It looks as though my battery loses
> about 3 Amp-Hours per week to parasitic current and self discharge. In
> reality, I should be able to go quite a long time if starting with a
> fully charged battery.
Battery University articles.
> Even though the charger/maintainer may not be doing the three phase
> saturation charge described on the website, the specific gravity has
> risen to 1.295 which is actually above the thresholds normally mentioned
> for full charge. I've heard that a lead-acid battery can still be fully
> charged at lower current but it will take longer.
accurate hydrometer. Your voltage reading seems high also. So there is
something strange going on with your charger and battery.
B&D gives very little information on the operation of their appliances. I'd
get a simple multimeter and check the operation. Verify the charging
current and the maintaining voltage.
There is very little you can do to change the operation of the B&D, but you
can get 15V, 3A supplies real cheap on eBay. Search for 15v 3a dc power
supply. Here are two at US $3.98
http://cgi.ebay.com/282331589635
http://cgi.ebay.com/311796300225
All you have to do is find the voltage setting resistor and drop it to
14.5V. eBay also has conventional power supplies with variable voltage and
current at higher prices.
If you don't have one already, you can get an inexpensive dvm. The DT830 is
an excellent unit. I usually buy 3 or 4 at a time. Here's one for US $2.83:
http://cgi.ebay.com/292064771224
I really like saturation charging. It is quick, it brings the battery to a
known full charge, and you can easily monitor the process to verify the
condition of the battery.
All we need to do now is command the alternator to put out the correct
voltage and keep it there.
kt77
Jul 21, 2017, 4:02:57 PM7/21/17
to
On Thursday, July 20, 2017 at 3:19:21 PM UTC-7, Steve Wilson wrote:
> Black & Decker gives very little information.
The Black & Decker 2 amp charger/maintainer does charge at 2 amps as measured by my VOM. The voltage varies depending on state of charge and surface charge. After going into maintain mode, my DVM typically sees 13.60-13.68 volts. I've seen the charge voltage drop and then rise which may be their method for detecting full charge. A portable radio placed near the charger indicates that a switcher is in use.
Black & Decker also sells a nice looking charger with meter which includes a battery recondition mode.
My voltage and specific gravity readings do seem a bit high but may just be the upper end of normal. The battery is essentially new with less than 900 miles on the car. The accuracy of my INNOVA DVM is stated to be 0.8% which could have a 12 volt reading off by 0.1 volts. My hydrometer is more than 50 years old and readings with other batteries was typically 1.265-1.285 which is normal for full charge. Readings do vary with temperature and also electrolyte level.
It turns out you can check a DVM against a fresh unused battery. Alkaline 1.58V, CR2032 Lithium 3.3V, Carbon Zinc Heavy Duty 1.62V. My DVM is very close on all three.
Several online sites discuss an Equalizing Charge which can lengthen the life of a lead acid battery. That process could be a help when the charging system does not keep a battery at full charge. An Equalizing Charge can reverse stratification within the electrolyte and help remove sulfate crystals.
> Black & Decker gives very little information.
The Black & Decker 2 amp charger/maintainer does charge at 2 amps as measured by my VOM. The voltage varies depending on state of charge and surface charge. After going into maintain mode, my DVM typically sees 13.60-13.68 volts. I've seen the charge voltage drop and then rise which may be their method for detecting full charge. A portable radio placed near the charger indicates that a switcher is in use.
Black & Decker also sells a nice looking charger with meter which includes a battery recondition mode.
My voltage and specific gravity readings do seem a bit high but may just be the upper end of normal. The battery is essentially new with less than 900 miles on the car. The accuracy of my INNOVA DVM is stated to be 0.8% which could have a 12 volt reading off by 0.1 volts. My hydrometer is more than 50 years old and readings with other batteries was typically 1.265-1.285 which is normal for full charge. Readings do vary with temperature and also electrolyte level.
It turns out you can check a DVM against a fresh unused battery. Alkaline 1.58V, CR2032 Lithium 3.3V, Carbon Zinc Heavy Duty 1.62V. My DVM is very close on all three.
Several online sites discuss an Equalizing Charge which can lengthen the life of a lead acid battery. That process could be a help when the charging system does not keep a battery at full charge. An Equalizing Charge can reverse stratification within the electrolyte and help remove sulfate crystals.
kt77
Jul 23, 2017, 4:58:56 PM7/23/17
to
On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
The Reserve Capacity marked on my battery is 125 minutes. I didn't realize it but you can calculate Amp-Hours by multiplying the Reserve Capacity by 0.4167 which in my case is 52 Amp-Hours.
"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
The Reserve Capacity marked on my battery is 125 minutes. I didn't realize it but you can calculate Amp-Hours by multiplying the Reserve Capacity by 0.4167 which in my case is 52 Amp-Hours.
k...@notreal.com
Jul 23, 2017, 5:15:37 PM7/23/17
to
On Sun, 23 Jul 2017 13:58:49 -0700 (PDT), kt77 <kawi...@gmail.com>
wrote:
>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>
>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>
>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
The chemistry is very similar.
>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
I haven't seen one for years. Not one where the consumer is supposed
to add water, anyway. Many have panels that can be pried off to add
water but I haven't seen an automotive battery with real filler ports
for decades.
>The Reserve Capacity marked on my battery is 125 minutes. I didn't realize it but you can calculate Amp-Hours by multiplying the Reserve Capacity by 0.4167 which in my case is 52 Amp-Hours.
"Reserve capacity" is defined as the time the battery will deliver 25A
so, of course AH can be derived from it. AH, at 25A, anyway. At
another current, the numbers will be different.
wrote:
>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>
>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>
>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
to add water, anyway. Many have panels that can be pried off to add
water but I haven't seen an automotive battery with real filler ports
for decades.
>The Reserve Capacity marked on my battery is 125 minutes. I didn't realize it but you can calculate Amp-Hours by multiplying the Reserve Capacity by 0.4167 which in my case is 52 Amp-Hours.
so, of course AH can be derived from it. AH, at 25A, anyway. At
another current, the numbers will be different.
Jasen Betts
Jul 24, 2017, 6:02:44 AM7/24/17
to
On 2017-07-23, k...@notreal.com <k...@notreal.com> wrote:
> On Sun, 23 Jul 2017 13:58:49 -0700 (PDT), kt77 <kawi...@gmail.com>
> wrote:
>
>>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>>
>>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>>
>>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
>
> The chemistry is very similar.
>
>>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
>
> I haven't seen one for years. Not one where the consumer is supposed
> to add water, anyway. Many have panels that can be pried off to add
> water but I haven't seen an automotive battery with real filler ports
> for decades.
I guess the market in your area doesn't trust customers with handling
> On Sun, 23 Jul 2017 13:58:49 -0700 (PDT), kt77 <kawi...@gmail.com>
> wrote:
>
>>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>>
>>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>>
>>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
>
> The chemistry is very similar.
>
>>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
>
> I haven't seen one for years. Not one where the consumer is supposed
> to add water, anyway. Many have panels that can be pried off to add
> water but I haven't seen an automotive battery with real filler ports
> for decades.
"chemicals" responsibly.
I've got two batteries here, an aftermarket Yuasa with integrated "Magic
Eye" (tm) hydrometer, flush screw-in filler caps with "coin" slots,
and a factory new battery (Suzuki) marked with an FB logo on one side,
(possibly Furukawa Battery) it has a translucent case with fill level
marked and knob-type filler caps, the label on the top has Japanese writing.
--
This email has not been checked by half-arsed antivirus software
k...@notreal.com
Jul 24, 2017, 8:25:19 PM7/24/17
to
On 24 Jul 2017 09:59:43 GMT, Jasen Betts <ja...@xnet.co.nz> wrote:
>On 2017-07-23, k...@notreal.com <k...@notreal.com> wrote:
>> On Sun, 23 Jul 2017 13:58:49 -0700 (PDT), kt77 <kawi...@gmail.com>
>> wrote:
>>
>>>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>>>
>>>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>>>
>>>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
>>
>> The chemistry is very similar.
>>
>>>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
>>
>> I haven't seen one for years. Not one where the consumer is supposed
>> to add water, anyway. Many have panels that can be pried off to add
>> water but I haven't seen an automotive battery with real filler ports
>> for decades.
>
>I guess the market in your area doesn't trust customers with handling
>"chemicals" responsibly.
No, they haven't been needed in decades. Maybe they are, now, since
>On 2017-07-23, k...@notreal.com <k...@notreal.com> wrote:
>> On Sun, 23 Jul 2017 13:58:49 -0700 (PDT), kt77 <kawi...@gmail.com>
>> wrote:
>>
>>>On Tuesday, July 18, 2017 at 7:54:19 PM UTC-7, kevin93 wrote:
>>>
>>>"Battery recharging in modern cars is complicated by the fact that in the effort to reduce weight, cost and maintenance the battery can't tolerate the high sustained voltage that older flooded cell batteries could. If the voltage is too high it will lose water and need topping up, which isn't easy with a maintenance-free battery or the thin grid will corrode excessively. Too low and the effects that have been described here become noticeable - so it's a compromise."
>>>
>>>Does this apply only to maintenance-free batteries? Many cars still have batteries with removable caps for adding distilled water.
>>
>> The chemistry is very similar.
>>
>>>My 2016 Toyota battery has removable caps and was manufactured by Johnson Controls. They have a very good reputation and supply batteries to Sears and several other brands.
>>
>> I haven't seen one for years. Not one where the consumer is supposed
>> to add water, anyway. Many have panels that can be pried off to add
>> water but I haven't seen an automotive battery with real filler ports
>> for decades.
>
>I guess the market in your area doesn't trust customers with handling
>"chemicals" responsibly.
the EPA is forcing such stupid rules.
kt77
Jul 25, 2017, 3:19:38 PM7/25/17
to
The removable caps I mentioned are the three-wide vent caps that you see on many batteries. The Sears website shows those caps on quite a few Diehard batteries described as Maintenance Free. That suggests that water might not need to be added over the life of the battery if operated under normal conditions and not overcharged.
In looking at the vent caps, I see a single slit that must be the vent for all three cells. My impression is that these caps trap at least some of the water vapor which eventually returns to the cells as water.
I've had several Sears Diehard batteries with these three-wide vent caps and did add small amounts of water on a fairly infrequent basis. The batteries generally lost more water during the summer months.
I had a feeling that my 2016 Toyota Battery was made by Johnson Controls based on the vent caps. They are the same vent caps I had on several Diehard batteries and also a NAPA Legend battery purchased fairly recently.
In looking at the vent caps, I see a single slit that must be the vent for all three cells. My impression is that these caps trap at least some of the water vapor which eventually returns to the cells as water.
I've had several Sears Diehard batteries with these three-wide vent caps and did add small amounts of water on a fairly infrequent basis. The batteries generally lost more water during the summer months.
I had a feeling that my 2016 Toyota Battery was made by Johnson Controls based on the vent caps. They are the same vent caps I had on several Diehard batteries and also a NAPA Legend battery purchased fairly recently.
kt77
Jul 31, 2017, 2:34:58 PM7/31/17
to
I've been considering getting a Conductance Battery Tester and ran across an exceptional video that I thought might be of interest. These devices inject an AC Current into the battery and do some analysis. You enter the CCA rating of your battery and the device tells you the actual capacity.
Battery Clinic - Part 3
https://www.youtube.com/watch?v=Oi8sUE9XCgA
This video provides a wealth of information and also shows the use of a 100 amp load tester and hydrometer.
The complete battery clinic consists of four videos. One of the videos discusses smart chargers and shows the results after using the recondition mode to remove sulfate deposits. One surprise is that several batteries measured over 13 volts presumably after dissipation of all surface charge. It was also mentioned that charging should be done at 7 amps or less.
Battery Clinic - Part 1
https://www.youtube.com/watch?v=uqs0FCJpjXU
Battery Clinic - Part 2
https://www.youtube.com/watch?v=KKSwwgY86D4
Battery Clinic - Part 4
https://www.youtube.com/watch?v=4PAyHIhK8g4
Many other videos are available from the same shop. One set shows how to replace the battery in a late model Mercedes without losing computer memory.
Battery Clinic - Part 3
https://www.youtube.com/watch?v=Oi8sUE9XCgA
This video provides a wealth of information and also shows the use of a 100 amp load tester and hydrometer.
The complete battery clinic consists of four videos. One of the videos discusses smart chargers and shows the results after using the recondition mode to remove sulfate deposits. One surprise is that several batteries measured over 13 volts presumably after dissipation of all surface charge. It was also mentioned that charging should be done at 7 amps or less.
Battery Clinic - Part 1
https://www.youtube.com/watch?v=uqs0FCJpjXU
Battery Clinic - Part 2
https://www.youtube.com/watch?v=KKSwwgY86D4
Battery Clinic - Part 4
https://www.youtube.com/watch?v=4PAyHIhK8g4
Many other videos are available from the same shop. One set shows how to replace the battery in a late model Mercedes without losing computer memory.
kt77
Aug 15, 2017, 3:45:52 PM8/15/17
to
Here is an update on my battery. I bought a Solar BA5 Conductance Tester which provides an estimated CCA rating. The tester is showing 655 CCA for my battery which is nominally rated at 582 CCA. The high reading does not entirely surprise me based on the high specific gravity and 12.85 V open circuit voltage. The battery is marked Toyota but made by Johnson Controls which is the supplier for Diehard and Interstate. The mileage on the car is currently less than 900 miles. I'd be interested if anyone else has tried one of these Conductance Testers.
I'm also attaching a chart showing my battery voltage versus time with a constant current charge of 2 amps. The battery was close to full charge at the start of the test.
https://postimg.org/image/p50uhjdwz/
You can see the battery voltage rise starting at 12.75 volts with the constant current charge. The battery voltage levels off a little above 14.2 volts. The battery is accumulating surface charge as the voltage rises which effectively increases the battery voltage. When the charger is disconnected, the voltage starts declining from the same elevated voltage and takes many hours to fully dissipate the surface charge.
Is this chart actually showing the sharp voltage threshold that Steve has mentioned when connecting a power supply to a battery? The chart seems to suggest that I would need a little over 14.2 volts if I wanted to charge at 2 amps after surface charge has reached equilibrium. The battery would represent a very low impedance load so the current would rise sharply whenever the power supply voltage exceeded the battery voltage plus surface charge and the voltage drop across internal resistance.
Steve wanted a higher charge current so the voltage threshold would be higher for that case and is apparently around 14.5 volts.
I believe the situation is different before the surface charge has reached equilibrium. In a vehicle, the battery is charged with a relatively constant voltage so the charge current would vary quite a bit. The charge current would likely be the highest right after starting the engine with no surface charge on the battery plates.
Note that if the charger had been constant voltage, the current would have declined as surface charge built up on the battery plates.
I'm also attaching a chart showing my battery voltage versus time with a constant current charge of 2 amps. The battery was close to full charge at the start of the test.
https://postimg.org/image/p50uhjdwz/
You can see the battery voltage rise starting at 12.75 volts with the constant current charge. The battery voltage levels off a little above 14.2 volts. The battery is accumulating surface charge as the voltage rises which effectively increases the battery voltage. When the charger is disconnected, the voltage starts declining from the same elevated voltage and takes many hours to fully dissipate the surface charge.
Is this chart actually showing the sharp voltage threshold that Steve has mentioned when connecting a power supply to a battery? The chart seems to suggest that I would need a little over 14.2 volts if I wanted to charge at 2 amps after surface charge has reached equilibrium. The battery would represent a very low impedance load so the current would rise sharply whenever the power supply voltage exceeded the battery voltage plus surface charge and the voltage drop across internal resistance.
Steve wanted a higher charge current so the voltage threshold would be higher for that case and is apparently around 14.5 volts.
I believe the situation is different before the surface charge has reached equilibrium. In a vehicle, the battery is charged with a relatively constant voltage so the charge current would vary quite a bit. The charge current would likely be the highest right after starting the engine with no surface charge on the battery plates.
Note that if the charger had been constant voltage, the current would have declined as surface charge built up on the battery plates.
Albert van der Horst
Dec 2, 2017, 1:12:35 PM12/2/17
to
In article <be098e53-ccbd-4fa5...@googlegroups.com>,
>d switched to maintain mode. The voltage read 14.26 volts at that point. T=
>hat voltage is consistent with the 14.2-14.5 volt range mentioned on the W8=
What do you see on an oscilloscope?
(Same remark about car alternators. High current peaks seem to
counter sulfation.)
Groetjes Albert
--
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst
kt77 <kawi...@gmail.com> wrote:
>On Tuesday, July 18, 2017 at 2:19:33 PM UTC-7, Steve Wilson wrote:
>
>> You still never made it to 14.5V
>> It looks like you need to put your battery on charge after every trip.
>
>The Black & Decker 2 amp battery charger/maintainer detected full charge an=
>On Tuesday, July 18, 2017 at 2:19:33 PM UTC-7, Steve Wilson wrote:
>
>> You still never made it to 14.5V
>> It looks like you need to put your battery on charge after every trip.
>
>d switched to maintain mode. The voltage read 14.26 volts at that point. T=
>hat voltage is consistent with the 14.2-14.5 volt range mentioned on the W8=
>JI website that I referenced earlier.
I'm not sure that the reading of a voltmeter says it all.
What do you see on an oscilloscope?
(Same remark about car alternators. High current peaks seem to
counter sulfation.)
Groetjes Albert
--
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst
kt77
Feb 9, 2018, 3:44:13 PM2/9/18
to
On Saturday, December 2, 2017 at 10:12:35 AM UTC-8, Albert van der Horst wrote:
> I'm not sure that the reading of a voltmeter says it all.
> What do you see on an oscilloscope?
> (Same remark about car alternators. High current peaks seem to
> counter sulfation.)
I wish I had an oscilloscope and could view the charging waveform. The charger does appear to use a switching regulator. Even so, I have a feeling that the average voltage and average current would still be meaningful in terms of charging the battery. This particular charger does not have a Desulfate Mode which would also be very interesting to view on an oscilloscope.
> I'm not sure that the reading of a voltmeter says it all.
> What do you see on an oscilloscope?
> (Same remark about car alternators. High current peaks seem to
> counter sulfation.)
That's a very interesting comment on alternator rectified current peaks helping to counter sulfation!
Here is a new data point that might be of interest. My car had not been driven for a full two weeks and the battery voltage only dropped to 12.59 volts. I connected the Black & Decker 2 Amp Charger/Maintainer and it stayed on charge for 3.25 hours. If the charger maintained 2 Amps during that period, it would have put 6.5 Amp Hours into the battery which is rated at 52 Amp Hours. That would suggest that the battery had a 12% discharge while sitting idle for two weeks. The battery had been fully charged prior to driving the car. Temperatures were in the range of 50-70 degrees F.
Steve Wilson
Feb 9, 2018, 5:29:37 PM2/9/18
to
kt77 <kawi...@gmail.com> wrote:
> On Saturday, December 2, 2017 at 10:12:35 AM UTC-8, Albert van der Horst
> wrote:
>> I'm not sure that the reading of a voltmeter says it all.
>> What do you see on an oscilloscope?
>> (Same remark about car alternators. High current peaks seem to counter
>> sulfation.)
> I wish I had an oscilloscope and could view the charging waveform. The
> charger does appear to use a switching regulator. Even so, I have a
> feeling that the average voltage and average current would still be
> meaningful in terms of charging the battery. This particular charger
> does not have a Desulfate Mode which would also be very interesting to
> view on an oscilloscope.
> That's a very interesting comment on alternator rectified current peaks
> helping to counter sulfation!
1. Sulfation occurs when the battery ls left discharged for a long time.
> On Saturday, December 2, 2017 at 10:12:35 AM UTC-8, Albert van der Horst
> wrote:
>> I'm not sure that the reading of a voltmeter says it all.
>> What do you see on an oscilloscope?
>> (Same remark about car alternators. High current peaks seem to counter
>> sulfation.)
> I wish I had an oscilloscope and could view the charging waveform. The
> charger does appear to use a switching regulator. Even so, I have a
> feeling that the average voltage and average current would still be
> meaningful in terms of charging the battery. This particular charger
> does not have a Desulfate Mode which would also be very interesting to
> view on an oscilloscope.
> That's a very interesting comment on alternator rectified current peaks
> helping to counter sulfation!
This is why you want to keep the battery fully charged.
2. when the engine is running, the alternator quickly charges the battery
to capacity, then the charging current drops to near zero, in the tens of
milliamperes range. Modern engines start so quickly that very little energy
is needed to start the car.
3. during charging, the battery only accepts current when the alterator
peaks are above the battery voltage. So it only charges in pulses on the
alternator peaks, and discharges the rest of the time to supply the normal
load (headlights, engine ignition, fuel injection, radio, heating and
cooling, cruise control, etc.) As long as the battery is fully charged, it
won't have any sulfation.
> Here is a new data point that might be of interest. My car had not been
> driven for a full two weeks and the battery voltage only dropped to
> 12.59 volts. I connected the Black & Decker 2 Amp Charger/Maintainer
> and it stayed on charge for 3.25 hours. If the charger maintained 2
> Amps during that period, it would have put 6.5 Amp Hours into the
> battery which is rated at 52 Amp Hours. That would suggest that the
> battery had a 12% discharge while sitting idle for two weeks. The
> battery had been fully charged prior to driving the car. Temperatures
> were in the range of 50-70 degrees F.
entry receiver, the burglar alarm system, etc. The battery drain is usually
less than 50 milliameres. If you let the car sit for two weeks, and the
drain was 50 mA, the total amp-hours would be
50e-3 * 24 * 14 = 16.8 amp-hours.
Since the B&D only put back 6.5 amp-hours, your idle current drain would be
(6.5 / 16.8) * 50e-3 = 1.93e-2 = 19.3 mA
However, we don't know how well the B&D is calibrated, and what condition
determines shutoff, so all estimates are only approximate.
But it looks like your battery and alternator are fine. Keep the charger so
you can help out your cute neighbour when she leaves an interior light on
overnight.
Tim Williams
Feb 10, 2018, 8:21:22 AM2/10/18
to
"Steve Wilson" <n...@spam.com> wrote in message
news:XnsA884B1F01F...@69.16.179.23...
I recently discovered that my driving pattern causes sulfation (seemingly,
not fatal). Frequent short starts to move the vehicle (~daily), infrequent
trips adequate to charge the battery (>10 mins).
It's just marginal enough (whether because of my driving pattern, or if it's
a weak alternator) that it takes 5 years to develop.
It's a '95, not a particularly new car, so it's missing some of the features
you noted.
Full recovery (in terms of ESR; capacity unknown) was obtained after
floating the battery at 14.4V for 48 hours. This drew very little current
overall, less than 10 amperes at first, dropping to 0.3A through the last
day.
Will see if it behaves for the rest of the winter (solid so far), and if it
still acts like new next winter.
Tim
--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: https://www.seventransistorlabs.com/
news:XnsA884B1F01F...@69.16.179.23...
> 1. Sulfation occurs when the battery ls left discharged for a long time.
> This is why you want to keep the battery fully charged.
>
> 2. when the engine is running, the alternator quickly charges the battery
> to capacity, then the charging current drops to near zero, in the tens of
> milliamperes range. Modern engines start so quickly that very little
> energy
> is needed to start the car.
<snip>
> This is why you want to keep the battery fully charged.
>
> 2. when the engine is running, the alternator quickly charges the battery
> to capacity, then the charging current drops to near zero, in the tens of
> milliamperes range. Modern engines start so quickly that very little
> energy
> is needed to start the car.
I recently discovered that my driving pattern causes sulfation (seemingly,
not fatal). Frequent short starts to move the vehicle (~daily), infrequent
trips adequate to charge the battery (>10 mins).
It's just marginal enough (whether because of my driving pattern, or if it's
a weak alternator) that it takes 5 years to develop.
It's a '95, not a particularly new car, so it's missing some of the features
you noted.
Full recovery (in terms of ESR; capacity unknown) was obtained after
floating the battery at 14.4V for 48 hours. This drew very little current
overall, less than 10 amperes at first, dropping to 0.3A through the last
day.
Will see if it behaves for the rest of the winter (solid so far), and if it
still acts like new next winter.
Tim
--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: https://www.seventransistorlabs.com/
Steve Wilson
Feb 10, 2018, 3:18:37 PM2/10/18
to
"Tim Williams" <tiw...@seventransistorlabs.com> wrote:
> I recently discovered that my driving pattern causes sulfation
> (seemingly, not fatal). Frequent short starts to move the vehicle
> (~daily), infrequent trips adequate to charge the battery (>10 mins).
> It's just marginal enough (whether because of my driving pattern, or if
> it's a weak alternator) that it takes 5 years to develop.
I'm retired and only drive 1,500 kilometers per year. It's a bunch of short
> I recently discovered that my driving pattern causes sulfation
> (seemingly, not fatal). Frequent short starts to move the vehicle
> (~daily), infrequent trips adequate to charge the battery (>10 mins).
> It's just marginal enough (whether because of my driving pattern, or if
> it's a weak alternator) that it takes 5 years to develop.
trips for groceries and parts from the hardware stores, with lots of
sitting in between. The battery is a couple of years old, and I often
monitor the quiescent voltage before starting. Oddly enough, the battery
measured 12.4 volts when I bought it instead of the normal 12.6 volts as
mentioned in numerous web sites such as the Battery University. It still
measures around 12.4 V, but varies with temperature.
I though the battery was bad when I purchased it, but it seems to be
holding up quite well. It has no trouble starting the car in -30c weather
after several days of cold soak.
I'm not surprised you are seeing a dropoff in capacity. Around here,
battery warranties seem to expire in 3 years, so they expect the battery to
die soon after. Most sites recommend a new battery after 6 years of
service, so you may be due for a new one.
I don't think you can attribute your performance to sulfation - the battery
has to be almost dead and sitting for guite some time. Then it won't accept
a charge.
I'd check the voltage under light and heavy loads. If there's not much
difference, your alternator is probably OK.
> It's a '95, not a particularly new car, so it's missing some of the
> features you noted.
> Full recovery (in terms of ESR; capacity unknown) was obtained after
> floating the battery at 14.4V for 48 hours. This drew very little
> current overall, less than 10 amperes at first, dropping to 0.3A through
> the last day.
and often charged at around 13.5 volts or less. I finally had to remove it
after each trip and put it on a constant current/constant voltage lab
supply.
I set the voltage to 14.5 Volts and 5 A. Like you, it measured 5 Amps at
the start, then it quickly dropped to several hundred mA after about 5
minutes. So I think the battery was OK.
How do you measure ESR?
olds...@tubes.com
Feb 10, 2018, 4:19:15 PM2/10/18
to
On Sat, 10 Feb 2018 20:18:31 GMT, Steve Wilson <n...@spam.com> wrote:
>My previous car was a Ford Taurus. It was designed to destroy the battery,
A mechanic once told me. There are TWO four letter "F-Words". He allows
>My previous car was a Ford Taurus. It was designed to destroy the battery,
his children to say the first one, but not the word FORD. (Unless the
first four letter F-Word, precedes the word FORD).
Phil Hobbs
Feb 10, 2018, 4:42:54 PM2/10/18
to
love) and a turbo-four Fusion (my wife's car, whose dashboard displays I
cordially dislike, but which makes her happy). No worries so far.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
https://hobbs-eo.com
Long Hair
Feb 10, 2018, 5:31:43 PM2/10/18
to
Steve Wilson wrote:
> How do you measure ESR?
>
Drive it through a known load and measure voltage and current at
> How do you measure ESR?
>
energization, and the ESR will be in series with that and should be
determinable with those instantaneous readings.
Doing so with small, medium, and heavy loads would allow one to dial
it in even more precisely.
kt77
Feb 10, 2018, 5:47:28 PM2/10/18
to
On Friday, February 9, 2018 at 2:29:37 PM UTC-8, Steve Wilson wrote:
> 2. when the engine is running, the alternator quickly charges the battery
> to capacity, then the charging current drops to near zero, in the tens of
> milliamperes range. Modern engines start so quickly that very little energy
> is needed to start the car.
I agree if the voltage regulator settings allow it. The problem today is that new cars are often light on charging to reduce alternator load and increase fuel economy. My car is in that category and the highest alternator voltage I've seen after a cold start is 14.25 volts and that was on a cold day. As soon as the engine warms up the voltage drops to the range of 13.5-13.8 volts. I may only see ten minutes where the charge current would be adequate for charging the battery. Ten minutes appears to be fine if the battery is in good condition and near full charge. It's a different story with a discharged battery or a sulfated battery. I think others have stated that automotive charging systems today are not designed to recharge a discharged battery.
> 2. when the engine is running, the alternator quickly charges the battery
> to capacity, then the charging current drops to near zero, in the tens of
> milliamperes range. Modern engines start so quickly that very little energy
> is needed to start the car.
I also wonder if there is a secondary problem with the temperature compensation typically used with voltage regulators. If I restart my car after a short trip, the engine is still warm and the alternator voltage may be 13.8 volts or less. The battery may still be relatively cool inside and need a higher alternator voltage to charge adequately.
Tim Williams
Feb 10, 2018, 6:12:43 PM2/10/18
to
<olds...@tubes.com> wrote in message
news:82ou7dhs9kpj4laur...@4ax.com...
Does it begin with F and end with U-C-K?
Although that's a nine letter word, hmm.
news:82ou7dhs9kpj4laur...@4ax.com...
Although that's a nine letter word, hmm.
Tim Williams
Feb 10, 2018, 6:25:57 PM2/10/18
to
"Steve Wilson" <n...@spam.com> wrote in message
news:XnsA8859BBAA9...@69.16.179.23...
> I'm not surprised you are seeing a dropoff in capacity. Around here,
> battery warranties seem to expire in 3 years, so they expect the battery
> to
> die soon after. Most sites recommend a new battery after 6 years of
> service, so you may be due for a new one.
I've seen figures of 10 years being typical, but I'm not sure if that was
> battery warranties seem to expire in 3 years, so they expect the battery
> to
> die soon after. Most sites recommend a new battery after 6 years of
> service, so you may be due for a new one.
because the people saying so were in more temperate climates.
I got 5 or 6 years out of the last battery (according to its sticker; I
didn't install it, it came with the car). Didn't try floating it,
unfortunately; might've been another year in it!
> I don't think you can attribute your performance to sulfation - the
> battery
> has to be almost dead and sitting for guite some time. Then it won't
> accept
> a charge.
(PbSO4 and Pb <--> Pb and PbO2), but that it's probably nonuniform enough to
cause problems (high ESR) but apparently not beyond the point of no return.
> I'd check the voltage under light and heavy loads. If there's not much
> difference, your alternator is probably OK.
Probably not far off, given that it's good for whole years at a time.
> How do you measure ESR?
>
ear. :^)
k...@notreal.com
Feb 10, 2018, 7:44:41 PM2/10/18
to
On Sat, 10 Feb 2018 16:42:42 -0500, Phil Hobbs
<pcdhSpamM...@electrooptical.net> wrote:
>On 02/10/2018 04:18 PM, olds...@tubes.com wrote:
>> On Sat, 10 Feb 2018 20:18:31 GMT, Steve Wilson <n...@spam.com> wrote:
>>
>>> My previous car was a Ford Taurus. It was designed to destroy the battery,
>>
>> A mechanic once told me. There are TWO four letter "F-Words". He allows
>> his children to say the first one, but not the word FORD. (Unless the
>> first four letter F-Word, precedes the word FORD).
>
>I have two of them, a convertible stick-shift Mustang (my car, which I
>love) and a turbo-four Fusion (my wife's car, whose dashboard displays I
>cordially dislike, but which makes her happy). No worries so far.
I have two, also. My wife's car is also a convertible Mustang (though
<pcdhSpamM...@electrooptical.net> wrote:
>On 02/10/2018 04:18 PM, olds...@tubes.com wrote:
>> On Sat, 10 Feb 2018 20:18:31 GMT, Steve Wilson <n...@spam.com> wrote:
>>
>>> My previous car was a Ford Taurus. It was designed to destroy the battery,
>>
>> A mechanic once told me. There are TWO four letter "F-Words". He allows
>> his children to say the first one, but not the word FORD. (Unless the
>> first four letter F-Word, precedes the word FORD).
>
>I have two of them, a convertible stick-shift Mustang (my car, which I
>love) and a turbo-four Fusion (my wife's car, whose dashboard displays I
>cordially dislike, but which makes her happy). No worries so far.
a 6-speed auto) and I drive an F-150 (bought both the same week ;-).
She had a Mercury Sable (same car as the Ford Taurus) and had no
problems with batteries. We were in Vermont at the time and got seven
years out of the original). Great vehicles. The only crappy Ford I've
had was the '73 Rustang-II (i.e. Pinto, in drag). OTOH, every Chrysler
product I've had was crap.
Phil Hobbs
Feb 10, 2018, 7:53:14 PM2/10/18
to
rusted out circa 2003. It had far and away the most comfortable seats
of any vehicle I've ever driven, and it was very reliable mechanically.
OTOH my '92 Saturn SC lasted twice as long before succumbing to
corrosion. (It was old enough to drive itself.)
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
k...@notreal.com
Feb 10, 2018, 8:14:02 PM2/10/18
to
On Sat, 10 Feb 2018 19:53:02 -0500, Phil Hobbs
through a head gasket every 30K miles (you could set a watch by it).
Both rusted out before 100K miles (about six years). The NE is hard
on car bodies but they weren't that much better than the Rustang-II.
I also had a '93 Eagle Vision TSI and a '96 Chrysler Intrepid. Nice
comfortable cars but they fell apart. The final nail for both was
transmissions.
<pcdhSpamM...@electrooptical.net> wrote:
>On 02/10/18 19:44, k...@notreal.com wrote:
>> On Sat, 10 Feb 2018 16:42:42 -0500, Phil Hobbs
>> <pcdhSpamM...@electrooptical.net> wrote:
>>
>>> On 02/10/2018 04:18 PM, olds...@tubes.com wrote:
>>>> On Sat, 10 Feb 2018 20:18:31 GMT, Steve Wilson <n...@spam.com> wrote:
>>>>
>>>>> My previous car was a Ford Taurus. It was designed to destroy the battery,
>>>>
>>>> A mechanic once told me. There are TWO four letter "F-Words". He allows
>>>> his children to say the first one, but not the word FORD. (Unless the
>>>> first four letter F-Word, precedes the word FORD).
>>>
>>> I have two of them, a convertible stick-shift Mustang (my car, which I
>>> love) and a turbo-four Fusion (my wife's car, whose dashboard displays I
>>> cordially dislike, but which makes her happy). No worries so far.
>>
>> I have two, also. My wife's car is also a convertible Mustang (though
>> a 6-speed auto) and I drive an F-150 (bought both the same week ;-).
>> She had a Mercury Sable (same car as the Ford Taurus) and had no
>> problems with batteries. We were in Vermont at the time and got seven
>> years out of the original). Great vehicles. The only crappy Ford I've
>> had was the '73 Rustang-II (i.e. Pinto, in drag). OTOH, every Chrysler
>> product I've had was crap.
>>
>
>We had a '94 Dodge Grand Caravan, which was great until it finally
>rusted out circa 2003. It had far and away the most comfortable seats
>of any vehicle I've ever driven, and it was very reliable mechanically.
I had '85 and a '90 voyagers. Both rusted badly. The '85 went
>On 02/10/18 19:44, k...@notreal.com wrote:
>> On Sat, 10 Feb 2018 16:42:42 -0500, Phil Hobbs
>> <pcdhSpamM...@electrooptical.net> wrote:
>>
>>> On 02/10/2018 04:18 PM, olds...@tubes.com wrote:
>>>> On Sat, 10 Feb 2018 20:18:31 GMT, Steve Wilson <n...@spam.com> wrote:
>>>>
>>>>> My previous car was a Ford Taurus. It was designed to destroy the battery,
>>>>
>>>> A mechanic once told me. There are TWO four letter "F-Words". He allows
>>>> his children to say the first one, but not the word FORD. (Unless the
>>>> first four letter F-Word, precedes the word FORD).
>>>
>>> I have two of them, a convertible stick-shift Mustang (my car, which I
>>> love) and a turbo-four Fusion (my wife's car, whose dashboard displays I
>>> cordially dislike, but which makes her happy). No worries so far.
>>
>> I have two, also. My wife's car is also a convertible Mustang (though
>> a 6-speed auto) and I drive an F-150 (bought both the same week ;-).
>> She had a Mercury Sable (same car as the Ford Taurus) and had no
>> problems with batteries. We were in Vermont at the time and got seven
>> years out of the original). Great vehicles. The only crappy Ford I've
>> had was the '73 Rustang-II (i.e. Pinto, in drag). OTOH, every Chrysler
>> product I've had was crap.
>>
>
>We had a '94 Dodge Grand Caravan, which was great until it finally
>rusted out circa 2003. It had far and away the most comfortable seats
>of any vehicle I've ever driven, and it was very reliable mechanically.
through a head gasket every 30K miles (you could set a watch by it).
Both rusted out before 100K miles (about six years). The NE is hard
on car bodies but they weren't that much better than the Rustang-II.
I also had a '93 Eagle Vision TSI and a '96 Chrysler Intrepid. Nice
comfortable cars but they fell apart. The final nail for both was
transmissions.
Phil Hobbs
Feb 10, 2018, 8:16:55 PM2/10/18
to
having to drive it any longer. ;)
Jim Thompson
Feb 10, 2018, 8:35:57 PM2/10/18
to
from Arizona or Southern California.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
It's what you learn, after you know it all, that counts.
Steve Wilson
Feb 10, 2018, 10:02:35 PM2/10/18
to
"Tim Williams" <tiw...@seventransistorlabs.com> wrote:
> "Steve Wilson" <n...@spam.com> wrote in message
> news:XnsA8859BBAA9...@69.16.179.23...
> "Steve Wilson" <n...@spam.com> wrote in message
> news:XnsA8859BBAA9...@69.16.179.23...
>> I don't think you can attribute your performance to sulfation - the
>> battery has to be almost dead and sitting for guite some time. Then it
>> won't accept a charge.
> "Sulfation" in a weak sense, in that, that's simply how a lead acid
> works (PbSO4 and Pb <--> Pb and PbO2), but that it's probably nonuniform
> enough to cause problems (high ESR) but apparently not beyond the point
> of no return.
> Tim
>> battery has to be almost dead and sitting for guite some time. Then it
>> won't accept a charge.
> "Sulfation" in a weak sense, in that, that's simply how a lead acid
> works (PbSO4 and Pb <--> Pb and PbO2), but that it's probably nonuniform
> enough to cause problems (high ESR) but apparently not beyond the point
> of no return.
The equation we are interested in is
Pb(s) + PbO2(s) + 2H2SO4(aq) --> 2PbSO4(s) + 2H2O(l)
Both plates get sulfated. This is not bad if the battery gets fully charged
before the sulfur crystals have time to harden. Here are some articles that
describe it better:
BU-804b: Sulfation and How to Prevent it
Applying ways to minimize sulfation.
Sulfation occurs when a lead acid battery is deprived of a full
charge. This is common with starter batteries in cars driven in the
city with load-hungry accessories. A motor in idle or at low speed
cannot charge the battery sufficiently.
Electric wheelchairs have a similar problem in that the users might
not charge the battery long enough. An 8-hour charge during the
night when the chair is not being used is not enough. Lead acid must
periodically be charged 14 - 16 hours to attain full saturation.
This may be the reason why wheelchair batteries last only 2 years,
whereas golf cars with the identical battery deliver twice the
service life. Long leisure time allows golf car batteries to get a
full charge overnight. (See 403: Charging Lead Acid.)
Solar cells and wind turbines do not always provide sufficient
charge for lead acid banks, which can lead to sulfation. This
happens in remote parts of the world where villagers draw generous
amounts of electricity with insufficient renewable resources to
charge the batteries. The result is a short battery life. Only a
periodic fully saturated charge can solve the problem. But without
an electrical grid at their disposal, this is almost impossible.
An alternative solution is using lithium-ion, a battery that prefers
a partial charge to a full charge. However, Li-ion is more than
double the cost of lead acid. Although more expensive, the cycle
count is said to be cheaper than that of lead acid because of the
extended service life.
What is sulfation? During use, small sulfate crystals form, but
these are normal and are not harmful. During prolonged charge
deprivation, however, the amorphous lead sulfate converts to a
stable crystalline and deposits on the negative plates. This leads
to the development of large crystals that reduce the battery's
active material, which is responsible for the performance.
There are two types of sulfation: reversible (or soft sulfation),
and permanent (or hard sulfation). If a battery is serviced early,
reversible sulfation can often be corrected by applying an
overcharge to an already fully charged battery in the form of a
regulated current of about 200mA. The battery terminal voltage is
allowed to rise to between 2.50 and 2.66V/cell (15 and 16V on a 12V
mono block) for about 24 hours. Increasing the battery temperature
to 50 - 60C (122 - 140F) during the corrective service further helps
in dissolving the crystals.
Permanent sulfation sets in when the battery has been in a low
state-of-charge for weeks or months. At this stage, no form of
restoration seems possible; however, the recovery yield is not fully
understood. To everyone's amazement, new lead acid batteries can
often be fully restored after dwelling in a low-voltage condition
for many weeks. Other factors may play a role.
A subtle indication whether lead acid can be recovered or not is
visible on the voltage discharge curve. If a fully charged battery
retains a stable voltage profile on discharge, chances of
reactivation are better than if the voltage drops rapidly with load.
Several companies offer anti-sulfation devices that apply pulses to
the battery terminals to prevent and reverse sulfation. Such
technologies will lower the sulfation on a healthy battery, but they
cannot effectively reverse the condition once present. It's a "one
size fits all" approach and the method is unscientific.
Applying random pulses or blindly inducing an overcharge can harm
the battery by promoting grid corrosion. There are no simple methods
to measure sulfation, nor are commercial chargers available that
apply a calculated overcharge to dissolve the crystals. As with
medicine, the most effective remedy is to apply a corrective service
for the time needed and not longer.
While anti-sulfation devices can reverse the condition, some battery
manufacturers do not recommend the treatment as it tends to create
soft shorts that may increase self-discharge. Furthermore, the
pulses contain ripple voltage that causes some heating of the
battery. Battery manufacturers specify the allowable ripple when
charging lead acid batteries.
Last updated 2016-09-22
http://batteryuniversity.com/index.php/learn/article/sulfation_and_how_to_p
revent_it
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Discharge
In the discharged state both the positive and negative plates become
lead(II) sulfate (PbSO4), and the electrolyte loses much of its
dissolved sulfuric acid and becomes primarily water. The discharge
process is driven by the conduction of electrons from the negative
plate back into the cell at the positive plate in the external
circuit.
The total reaction can be written as
Pb(s) + PbO2(s) + 2H2SO4(aq) --> 2PbSO4(s) + 2H2O(l)
Sulfation and desulfation
Lead - acid batteries lose the ability to accept a charge when
discharged for too long due to sulfation, the crystallization of
lead sulfate.[27] They generate electricity through a double sulfate
chemical reaction. Lead and lead dioxide, the active materials on
the battery's plates, react with sulfuric acid in the electrolyte to
form lead sulfate. The lead sulfate first forms in a finely divided,
amorphous state, and easily reverts to lead, lead dioxide and
sulfuric acid when the battery recharges. As batteries cycle through
numerous discharges and charges, some lead sulfate is not recombined
into electrolyte and slowly converts to a stable crystalline form
that no longer dissolves on recharging. Thus, not all the lead is
returned to the battery plates, and the amount of usable active
material necessary for electricity generation declines over time.
Sulfation occurs in lead - acid batteries when they are subjected to
insufficient charging during normal operation. It impedes
recharging; sulfate deposits ultimately expand, cracking the plates
and destroying the battery. Eventually so much of the battery plate
area is unable to supply current that the battery capacity is
greatly reduced. In addition, the sulfate portion (of the lead
sulfate) is not returned to the electrolyte as sulfuric acid. It is
believed that large crystals physically block the electrolyte from
entering the pores of the plates. Sulfation can be avoided if the
battery is fully recharged immediately after a discharge cycle.[28]
A white coating on the plates may be visible (in batteries with
clear cases, or after dismantling the battery). Batteries that are
sulfated show a high internal resistance and can deliver only a
small fraction of normal discharge current. Sulfation also affects
the charging cycle, resulting in longer charging times, less
efficient and incomplete charging, and higher battery temperatures.
SLI batteries (starting, lighting, ignition; ie, car batteries)
suffer most deterioration because vehicles normally stand unused for
relatively long periods of time. Deep cycle and motive power
batteries are subjected to regular controlled overcharging,
eventually failing due to corrosion of the positive plate grids
rather than sulfation.
There are no known, independently verified ways to reverse
sulfation.[8][29] There are commercial products claiming to achieve
desulfation through various techniques (such as pulse charging), but
there are no peer-reviewed publications verifying their claims.
Sulfation prevention remains the best course of action, by
periodically fully charging the lead-acid batteries.
https://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery
So when you go to Walmart or some other battery store, you may see racks of
batteries waiting to be sold. The reason they don't sulfate is because they
were fully charged before being placed on the racks, and they don't stay
there long enough to become discharged.
Steve Wilson
Feb 10, 2018, 10:45:49 PM2/10/18
to
through loss of coolant. Here is the story:
https://silvercell.000webhostapp.com/car/taurus.htm
A fiendish wicked design. It is now 2018. I don't see any more on the road
these days. They either rusted out or lost the engine.
Steve Wilson
Feb 10, 2018, 11:05:05 PM2/10/18
to
kt77 <kawi...@gmail.com> wrote:
> On Friday, February 9, 2018 at 2:29:37 PM UTC-8, Steve Wilson wrote:
>> 2. when the engine is running, the alternator quickly charges the
>> battery
>> to capacity, then the charging current drops to near zero, in the tens
>> of
>> milliamperes range. Modern engines start so quickly that very little
>> ener gy is needed to start the car.
> On Friday, February 9, 2018 at 2:29:37 PM UTC-8, Steve Wilson wrote:
>> 2. when the engine is running, the alternator quickly charges the
>> battery
>> to capacity, then the charging current drops to near zero, in the tens
>> of
>> milliamperes range. Modern engines start so quickly that very little
> I agree if the voltage regulator settings allow it. The problem today
> is that new cars are often light on charging to reduce alternator load
> and increase fuel economy. My car is in that category and the highest
> alternator voltage I've seen after a cold start is 14.25 volts and that
> was on a cold day. As soon as the engine warms up the voltage drops to
> the range of 13.5-13.8 volts. I may only see ten minutes where the
> charge current would be adequate for charging the battery. Ten minutes
> appears to be fine if the battery is in good condition and near full
> charge. It's a different story with a discharged battery or a sulfated
> battery. I think others have stated that automotive charging systems
> today are not designed to recharge a discharged battery.
> I also wonder if there is a secondary problem with the temperature
> compensation typically used with voltage regulators. If I restart my
> car after a short trip, the engine is still warm and the alternator
> voltage may be 13.8 volts or less. The battery may still be relatively
> cool inside and need a higher alternator voltage to charge adequately.
starting the engine. The actual drain current to keep the battery charged
is very low. However, when you have a high load current from headlights,
heatd seats, rear window defrost, stereo, and other loads, the alternator
only charges on the peaks, and the battery has to supply the total load
current between the peaks.
The alternator output is three phase bridge rectified, so there are 6
voltage peaks per cycle. This means the ripple voltage is pretty low, so
the alternator is taking the full load for a large part of the cycle. But
the battery has to supply the load the rest of the time, and it needs to be
in good shape. Especially if you are stuck in traffic at night with the
healights on and the air conditioning full on. My battery died in Toronto
one night under these same conditions, and it was a real pain trying to get
it out of the traffic and get the engine started again.
Older cars had the voltage regulator inside the alternator. Since the
alternator was bolted to the engine, it quickly attained the heat from the
engine. After warmup, the regulator reduced the charging voltage regardless
of the actual battery temperature. The battery became depleted and would
begin to sulfate. This happened on my old Taurus.
Newer cars meaure the intake manifold air temperature to estimate the
battery temperature. This is a bit more accurate, but the temperature
sensor can absorb heat from the engine while you are shopping. This throws
off the estimate of battery temperature and the battery can be overcharged
or undercharged depending on conditions.
Phil Hobbs
Feb 11, 2018, 9:12:39 AM2/11/18
to
Hyundai XG350 because the fenders rusted out, but it had 180k on it and
didn't owe us anything--apart from one engine computer and a set of
struts it worked fine till the day we traded it in on the Fusion.
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