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How to charge a 6V Gel Cell
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boomer#...@none.com
Apr 22, 2015, 4:23:58 AM4/22/15
to
How to charge a Gel Cell 6V 4.5Ah.
I have an electric fence charger (fencer) for livestock. It has a solar
panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
used for several years, so the battery is completely discharged. It's
likely I'll need to replace the battery, but whether the battery is
completely discharged, or brand new, I was told the battery should be
pre-charged before use, because the solar panel is only meant to keep
the battery at full charge.
They sell a charger for these batteries, but from the pictures, it's
nothing but a wall-wart, and they want a hefty price for them.
Can I use any 6 volt DC wall-wart?
(I think I have a few in my parts boxes).
I also have a small standard 4amp automotive battery charger with a 6
volt and 12 volt switch on it. Can I just set it to the 6volt position
and use that? Yes, I know the voltage is correct, but I'm wondering if
the amperage is too high for a small battery like this?
I was told they are actually lead-acid batteries, but contain th eacid
in a gell..... (this may or may not be right).
By the way, I'm no good with math.
I know AH means Amp-Hour, but how does that convert to actual amps?
I never understood the "hour" part....
Does 4.5 AH mean it puts out a maximim of 4amps for one full hour, or
what?
Thanks
I have an electric fence charger (fencer) for livestock. It has a solar
panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
used for several years, so the battery is completely discharged. It's
likely I'll need to replace the battery, but whether the battery is
completely discharged, or brand new, I was told the battery should be
pre-charged before use, because the solar panel is only meant to keep
the battery at full charge.
They sell a charger for these batteries, but from the pictures, it's
nothing but a wall-wart, and they want a hefty price for them.
Can I use any 6 volt DC wall-wart?
(I think I have a few in my parts boxes).
I also have a small standard 4amp automotive battery charger with a 6
volt and 12 volt switch on it. Can I just set it to the 6volt position
and use that? Yes, I know the voltage is correct, but I'm wondering if
the amperage is too high for a small battery like this?
I was told they are actually lead-acid batteries, but contain th eacid
in a gell..... (this may or may not be right).
By the way, I'm no good with math.
I know AH means Amp-Hour, but how does that convert to actual amps?
I never understood the "hour" part....
Does 4.5 AH mean it puts out a maximim of 4amps for one full hour, or
what?
Thanks
mike
Apr 22, 2015, 2:02:37 PM4/22/15
to
On 4/22/2015 1:21 AM, boomer#687...@none.com wrote:
> How to charge a Gel Cell 6V 4.5Ah.
>
> I have an electric fence charger (fencer) for livestock. It has a solar
> panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
> used for several years, so the battery is completely discharged. It's
> likely I'll need to replace the battery, but whether the battery is
> completely discharged, or brand new, I was told the battery should be
> pre-charged before use, because the solar panel is only meant to keep
> the battery at full charge.
>
> They sell a charger for these batteries, but from the pictures, it's
> nothing but a wall-wart, and they want a hefty price for them.
>
> Can I use any 6 volt DC wall-wart?
> (I think I have a few in my parts boxes).
>
> I also have a small standard 4amp automotive battery charger with a 6
> volt and 12 volt switch on it. Can I just set it to the 6volt position
> and use that? Yes, I know the voltage is correct, but I'm wondering if
> the amperage is too high for a small battery like this?
If you're worried about the amps, put a car tail light in series.
> How to charge a Gel Cell 6V 4.5Ah.
>
> I have an electric fence charger (fencer) for livestock. It has a solar
> panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
> used for several years, so the battery is completely discharged. It's
> likely I'll need to replace the battery, but whether the battery is
> completely discharged, or brand new, I was told the battery should be
> pre-charged before use, because the solar panel is only meant to keep
> the battery at full charge.
>
> They sell a charger for these batteries, but from the pictures, it's
> nothing but a wall-wart, and they want a hefty price for them.
>
> Can I use any 6 volt DC wall-wart?
> (I think I have a few in my parts boxes).
>
> I also have a small standard 4amp automotive battery charger with a 6
> volt and 12 volt switch on it. Can I just set it to the 6volt position
> and use that? Yes, I know the voltage is correct, but I'm wondering if
> the amperage is too high for a small battery like this?
It's possible that the charger voltage is too high for long-term
charging, but should be ok if you turn it off when it's fully charged.
Frank Miles
Apr 22, 2015, 3:51:11 PM4/22/15
to
On Wed, 22 Apr 2015 03:21:55 -0500, boomer#6877250 wrote:
> How to charge a Gel Cell 6V 4.5Ah.
>
> I have an electric fence charger (fencer) for livestock. It has a solar
> panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
> used for several years, so the battery is completely discharged. It's
> likely I'll need to replace the battery, but whether the battery is
> completely discharged, or brand new, I was told the battery should be
> pre-charged before use, because the solar panel is only meant to keep
> the battery at full charge.
You haven't given us enough information about the capacity of the solar
> How to charge a Gel Cell 6V 4.5Ah.
>
> I have an electric fence charger (fencer) for livestock. It has a solar
> panel to charge the 6V 4.5Ah Gel Cell. But this fencer has not been
> used for several years, so the battery is completely discharged. It's
> likely I'll need to replace the battery, but whether the battery is
> completely discharged, or brand new, I was told the battery should be
> pre-charged before use, because the solar panel is only meant to keep
> the battery at full charge.
panel to evaluate.
>
> They sell a charger for these batteries, but from the pictures, it's
> nothing but a wall-wart, and they want a hefty price for them.
>
> Can I use any 6 volt DC wall-wart?
> (I think I have a few in my parts boxes).
Most "6V" gel cells are closer to 7.2V at full charge. 6V is not enough.
> They sell a charger for these batteries, but from the pictures, it's
> nothing but a wall-wart, and they want a hefty price for them.
>
> Can I use any 6 volt DC wall-wart?
> (I think I have a few in my parts boxes).
Of course if you have an 'unregulated' wall wart it might work so long as
you're lucky and its sized appropriately.
> I also have a small standard 4amp automotive battery charger with a 6
> volt and 12 volt switch on it. Can I just set it to the 6volt position
> and use that? Yes, I know the voltage is correct, but I'm wondering if
> the amperage is too high for a small battery like this?
> I was told they are actually lead-acid batteries, but contain th eacid
> in a gell..... (this may or may not be right).
should charge a a safe voltage. If it's smarter, it will probably be
mostly ok but switch from "fast" charging to "float" too early.
> By the way, I'm no good with math.
> I know AH means Amp-Hour, but how does that convert to actual amps?
> I never understood the "hour" part....
>
> Does 4.5 AH mean it puts out a maximim of 4amps for one full hour, or
> what?
constant current "I" amps for some time "T" hours that you should expect
to get some useful voltage as long as I*T < 4.5. YMMV!
Good luck...
mrob...@att.net
Apr 22, 2015, 6:02:55 PM4/22/15
to
boomer#687...@none.com wrote:
> It's likely I'll need to replace the battery, but whether the battery
> is completely discharged, or brand new, I was told the battery should
> be pre-charged before use, because the solar panel is only meant to
> keep the battery at full charge.
Charging a new battery before use is a good idea anyway. It was
> It's likely I'll need to replace the battery, but whether the battery
> is completely discharged, or brand new, I was told the battery should
> be pre-charged before use, because the solar panel is only meant to
> keep the battery at full charge.
probably given a full or nearly full charge at the factory, but you
don't know how long it's been sitting around before you got ahold of it.
> They sell a charger for these batteries, but from the pictures, it's
> nothing but a wall-wart, and they want a hefty price for them.
without any regulation or other control, other than the maximum current
they can put out. Some of them are regulated, and some of them even
charge in two or more stages, to help speed up charging.
Mouser sells a two-stage one for $30 plus shipping:
http://www.mouser.com/ProductDetail/Power-Sonic/PSC-6500A-C/?qs=sGAEpiMZZMsYfYypWaYaEX3NNwy%2fyo1X2dL7Jr4fR1U%3d
<http://www.mouser.com/ProductDetail/Power-Sonic/PSC-6500A-C/?qs=sGAEpiMZZMsYfYypWaYaEX3NNwy%2fyo1X2dL7Jr4fR1U%3d>
> Can I use any 6 volt DC wall-wart?
> (I think I have a few in my parts boxes).
voltage of the battery, whether the battery is discharged or fully
charged, it will work. Also, the maximum current it actually delivers
should not exceed the maximum recommended value for your battery.
One manufacturer (Power-Sonic) recommends charging at 7.35 V and at not
more than 0.9 A (for your battery), until the current drops to 0.045
mA (for your battery), and then stopping the charge. Alternatively, if
you want to leave it on charge "continuously", you can charge at 6.75 V.
If the battery you get is very discharged, what will probably happen is
that one of your wall-warts will be under the limits at first, but as
the battery starts to charge, it will exceed the voltage limit. If the
charge current is fairly low when the voltage limit has been exceeded,
the solar panel may be able to bring it up to full. Clean the dust and
dirt off the panel and set it outside on a sunny day and hope for the
best. (Once the fencer is installed, it's a good idea to wipe the
panel off once a month or so, if you can reach it.)
> I also have a small standard 4amp automotive battery charger with a 6
> volt and 12 volt switch on it. Can I just set it to the 6volt position
> and use that? Yes, I know the voltage is correct, but I'm wondering
> if the amperage is too high for a small battery like this?
charger on the "6 volt" setting may cause the battery to draw more than
the 0.9 A limit for your battery. It won't hurt much to try it for a
few seconds and see... put a good ammeter (like, built into a
multimeter) in series with the output of the charger. Don't rely on the
built-in meter on the charger, if it has one.
If the battery charger (or wall-wart) voltage is just a little too high,
you could put a single diode in series with the output to drop the
voltage by about 1.1 V (for a regular rectifier diode, 1N4001 or 1N5624)
or about 0.5 V (for a Schottky diode, 1N5820). These diodes are
available from Digi-Key or Mouser for 20 or 30 cents, quantity one.
You might also be able to use a power resistor in series with the
battery charger output to tame its output a little, but you'll have to
experiment a to find out if this will work. The single filament of an
1156 or 3056 car tail light lamp, or the "bright" filament of an 1157 or
3057 lamp, may work.
> I was told they are actually lead-acid batteries, but contain the acid
> in a gell..... (this may or may not be right).
the acid in a porous fiberglass mat; the term "absorbed glass mat" or
"AGM" is probably more correct. If you say "gel cell", everybody knows
what you mean.
> Does 4.5 AH mean it puts out a maximim of 4amps for one full hour, or
> what?
that for a 4.5 Ah battery that is fully charged, you can get 0.225 A
from it, continuously, for 20 hours, and then it will be completely
discharged. 0.225 A * 20 h = 4.5 Ah.
It scales up and down from this, but the scale is not quite linear. It
works in your favor if you hit the battery less hard than the "20 hour"
discharge rate. If you draw half the current (0.113 A), you get a
little more than twice the runtime (say, 42 hours or so). It works
against you if you hit the battery harder than the "20 hour" discharge
rate; if you draw twice the current (0.45 A), you get less than half of
the runtime - about 9 hours. If you draw ten times the current (2.25 A),
you get much less than 1/10th of the runtime - about 1.3 hours.
For batteries like this, I usually order from Digi-Key (Panasonic brand)
or Mouser (Power-Sonic brand). I've been unhappy with every other brand
that I've tried. I should note that for many years the Power-Sonics I
got were built in Mexico, but the most recent set were from China. That
set has only been in service in a UPS for a couple of years, so I don't
know yet how long they will last. Mostly I use them as replacements in
computer UPSes, but some of them have gone in things like portable
lanterns.
Even if you don't plan on buying from Digi-Key or Mouser, it is good to
get a reference price from them. If you see a seller somewhere else
(usually eBay or Amazon) claiming to sell the same brand at way less
than the Digi-Key or Mouser price, scroll way down and look at the fine
print. It probably says "compatible replacement" or other words that
mean you're getting a junk battery rather than the real thing.
If you're ever stuck and need one right now, today, go look in the
electrical aisle at Home Depot, near the EXIT signs that they sell.
They have a few sizes that are made to go in those signs. A local fire
and burglar alarm company will also stock a few sizes, but they may or
may not want to sell you one over the counter.
Standard disclaimers apply: I don't get money or other consideration
from any companies mentioned.
Matt Roberds
mrob...@att.net
Apr 22, 2015, 6:57:06 PM4/22/15
to
mrob...@att.net wrote:
> One manufacturer (Power-Sonic) recommends charging at 7.35 V and at not
> more than 0.9 A (for your battery), until the current drops to 0.045
> mA (for your battery), and then stopping the charge.
CORRECTION: until the current drops to 0.045 *A*, or 45 mA.
> One manufacturer (Power-Sonic) recommends charging at 7.35 V and at not
> more than 0.9 A (for your battery), until the current drops to 0.045
> mA (for your battery), and then stopping the charge.
Matt Roberds
daku...@gmail.com
Apr 23, 2015, 1:07:47 AM4/23/15
to
for 1 hour, or 2.25A for 2 hours, etc., before
a re-charge. 'AH' us Ampere-Hour and is a
measure of battery capacity. A charger should
be able to supply a maximum of 450 mA. Why not
just design and build a simple linear power
supply for the fence, from COTS components,
using the rated current/voltage for the fence.
Hope that helps.
Kevin McMurtrie
Apr 23, 2015, 2:35:05 AM4/23/15
to
In article <fbmejat18lhgjfoij...@4ax.com>,
You can buy smart chargers online. There are essentially two types of
charging:
Cycle : Apply 6.8V If current is drawn, charge with limited current to
7.2V until current falls to 45mA. Return to 6.8V. Charge will reach
nearly 100%.
Float : Hold at 6.9V. Charge will reach 70% then very slowly climb to
80% or more.
Solar charging with the fence always on would be similar to cycle
charging since the battery will only approach full charge near the end
of the day. Just shunt the voltage to 7.2V.
If the fence is not always on, shunt to 6.9V.
4.5 AH for gel cell means that it should average 225 mA over 20 hours.
--
I will not see posts from astraweb, theremailer, dizum, or google
because they host Usenet flooders.
charging:
Cycle : Apply 6.8V If current is drawn, charge with limited current to
7.2V until current falls to 45mA. Return to 6.8V. Charge will reach
nearly 100%.
Float : Hold at 6.9V. Charge will reach 70% then very slowly climb to
80% or more.
Solar charging with the fence always on would be similar to cycle
charging since the battery will only approach full charge near the end
of the day. Just shunt the voltage to 7.2V.
If the fence is not always on, shunt to 6.9V.
4.5 AH for gel cell means that it should average 225 mA over 20 hours.
--
I will not see posts from astraweb, theremailer, dizum, or google
because they host Usenet flooders.
DemonicTubes
Apr 24, 2015, 1:10:07 PM4/24/15
to
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