Lithium iron phosphate battery selection

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bob prohaska

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Mar 24, 2022, 10:01:07 PMMar 24
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Any suggestions for vendors of packaged LiPO4 batteries?
There are lots of brand names for 12 volt 100 amp hour
units, but very little guidance on relative value and
reliability. This particular application is for a trolling
motor, I'm looking mostly for guidance on reputable sellers.

Thanks for reading
bob prohaska


Jim Wilkins

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Mar 25, 2022, 8:02:10 AMMar 25
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"bob prohaska" wrote in message news:t1j7p1$f19$1...@dont-email.me...
--------------

Sorry, not from me. I tested Lithiums in industry but didn't select or
purchase them. At home I have almost entirely second-hand or NOS laptop and
cell charger Lithiums, since new ones cost so much and I've paid good money
for low-capacity fakes. The proper person to ask would handle warranty
returns, perhaps at a store.
https://www.healthcabin.net/blog/5-easy-ways-to-spot-a-counterfeit-18650-battery/

The numerous in-house machines at Segway used older degraded (free)
batteries so I know they do lose capacity, but we didn't keep records on
them. In my experience Lithiums' loss of capacity is somewhat random, which
on-line reviews may reflect.

Jim Wilkins

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Mar 25, 2022, 7:55:47 PMMar 25
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"bob prohaska" wrote in message news:t1j7p1$f19$1...@dont-email.me...

------------------------

The 12V 100Ah Ampere Time on Amazon has >1000 good reviews and a low (for
Lithium) price.
The max discharge current is 100A. How much does your motor need?
https://www.trollingmotors.net/blogs/selection/86961351-calculating-motor-run-time

Email: ser...@amperetime.com

TEL: (+86) 0755 2850 3270 Monday to Friday 9am - 6pm (HKT)

That's all I know. I'm watching them too but they aren't close to cost
competitive with flooded lead-acid for backup solar yet. They might be for
daily cycling if they deliver their promised cycle life.

bob prohaska

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Mar 25, 2022, 9:10:14 PMMar 25
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It turns out Costco has these on (very short) sale:
https://www.costco.com/lion-energy-safari-ut1300-2-pack.product.100663833.html
I'm not a Costco member, so I can't see the price, but from what I gather
Costco _usually_ offer at least decent products for the money and has a
relatively generous return policy.

Thanks for reading!

bob prohaska



danny burstein

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Mar 25, 2022, 9:23:35 PMMar 25
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In <t1lp5k$dn0$1...@dont-email.me> bob prohaska <b...@www.zefox.net> writes:

[snip]

>It turns out Costco has these on (very short) sale:
>https://www.costco.com/lion-energy-safari-ut1300-2-pack.product.100663833.html
>I'm not a Costco member, so I can't see the price, but from what I gather
>Costco _usually_ offer at least decent products for the money and has a
>relatively generous return policy.

For the hell of it, I just logged in and..

it's 1,399.99

Note this is a two pack.

(I'm looking for a two pack of 25 to 30 amp hour ones
to retrofit my Amigo brand Amigo scooter)



--
_____________________________________________________
Knowledge may be power, but communications is the key
dan...@panix.com
[to foil spammers, my address has been double rot-13 encoded]

Jim Wilkins

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Mar 26, 2022, 6:39:32 AMMar 26
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"danny burstein" wrote in message news:t1lpul$459$1...@reader1.panix.com...

In <t1lp5k$dn0$1...@dont-email.me> bob prohaska <b...@www.zefox.net> writes:

[snip]

>It turns out Costco has these on (very short) sale:
>https://www.costco.com/lion-energy-safari-ut1300-2-pack.product.100663833.html
>I'm not a Costco member, so I can't see the price, but from what I gather
>Costco _usually_ offer at least decent products for the money and has a
>relatively generous return policy.

For the hell of it, I just logged in and..

it's 1,399.99

Note this is a two pack.

(I'm looking for a two pack of 25 to 30 amp hour ones
to retrofit my Amigo brand Amigo scooter)

------------------
Elsewhere they are $849-$899 each.
https://shopsolarkits.com/blogs/learning-center/lion-energy-safari-ut-1300-review

Jim Wilkins

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Mar 26, 2022, 10:34:46 AMMar 26
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"danny burstein" wrote in message news:t1lpul$459$1...@reader1.panix.com...

In <t1lp5k$dn0$1...@dont-email.me> bob prohaska <b...@www.zefox.net> writes:

[snip]

>It turns out Costco has these on (very short) sale:
>https://www.costco.com/lion-energy-safari-ut1300-2-pack.product.100663833.html
>I'm not a Costco member, so I can't see the price, but from what I gather
>Costco _usually_ offer at least decent products for the money and has a
>relatively generous return policy.

For the hell of it, I just logged in and..

it's 1,399.99

Note this is a two pack.

(I'm looking for a two pack of 25 to 30 amp hour ones
to retrofit my Amigo brand Amigo scooter)

-------------------------
Does the Amigo take the U1 size? My experience with several brands is that
they degrade rapidly if not kept near fully charged, but last several/many
years with adequate care. Sitting unused can let them become "sulfated"
where they won't accept much current at the normal charging voltage and
appear dead, but they can often be restored with a higher current-limited
voltage from an adjustable power supply. I haven't tried pulse desulfators.

https://goodoldboat.com/equalizing-batteries/
"In this process the batteries are brought to full charge, then the charge
voltage is increased to a much higher level than usual, typically between 15
and 16 volts, to overcome the higher internal resistance caused by the
sulfation. To prevent cooking the batteries, the current is limited to
between 5 and 10 percent of the battery’s amp-hour capacity. This voltage is
then held for several hours."

This is a versatile metered variable supply that I use to equalize 24V
batteries with power from a 12V solar system:
https://www.amazon.com/Adjustable-Regulator-DROK-Converter-6-0V-36V/dp/B089ND7PTH?ref_=ast_sto_dp

Its DC input can be whatever you have, such as an old 19V laptop power
supply. Since equalizing generates hydrogen it's better done outdoors, and
check the water level afterwards.
It seems to be both less necessary and less effective on AGMs.

danny burstein

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Mar 26, 2022, 11:17:36 AMMar 26
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In <t1n8a4$fm$1...@dont-email.me> "Jim Wilkins" <murat...@gmail.com> writes:

[snip]

>(I'm looking for a two pack of 25 to 30 amp hour ones
>to retrofit my Amigo brand Amigo scooter)

>-------------------------
>Does the Amigo take the U1 size? My experience with several brands is that
>they degrade rapidly if not kept near fully charged, but last several/many
>years with adequate care. Sitting unused can let them become "sulfated"
>where they won't accept much current at the normal charging voltage and
>appear dead, but they can often be restored with a higher current-limited
>voltage from an adjustable power supply. I haven't tried pulse desulfators.

There are slots next to the seat which hold two AGM batteries
that are a bit smaller than U1, namely 7 x 3 x 6.75 (approx).

This is pretty standard.

The "claimed" capacity is (depending on specific unit) 20 Amp-hrs
for AGM.

The less I say about labels and garbage the better. the
number I see is more like 10 amp-hrs. I've been pretty
careful about charging...

The original OEM charger is a 24 Volt unit of unknown specs
which plugged into the side.

One day it died and I simply picked up a Battery Tender brand
Battery Tender.. and clip it on the batteries directly. I
discovered it gets me about 20 percent more effective time.

What I'm doing these days is have the two batteries in
the slots, AND ALSO another two sitting on the foot rest.

I run off the latter units, which usually gets me through
the day, and, if needed, swap cords into the other two.

(One of these days I'll set up a switch).

And yeah, I top off all the batteries in my stable
about once/month.

Given the "real" capacity seems to be
half the listed number
I've been waiting and watching for
the li-ion ones to drop in price..
Oh, they also weigh
a LOT less.

Thanks

Jim Wilkins

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Mar 26, 2022, 1:03:35 PMMar 26
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"danny burstein" wrote in message news:t1naqe$1oe$1...@reader1.panix.com...
-------------------------------------
I have two 12V 18Ah AGMs in parallel running the freezer right now, being
fully charged by the solar panels before I put one in a dying Harbor Freight
5-in-1 power pack. They are over 5 years old and retain 30Ah of capacity,
which is unusual, some have died in 3 years.

Jim Wilkins

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Mar 26, 2022, 8:36:04 PMMar 26
to
"Jim Wilkins" wrote in message news:t1nh16$g0v$1...@dont-email.me...

I have two 12V 18Ah AGMs in parallel running the freezer right now, being
fully charged by the solar panels before I put one in a dying Harbor Freight
5-in-1 power pack. ...
--------------------------
I pulled the original 2011 12V 18Ah ShengWei AGM battery out of the HF
5-in-1 and tested it. On the carbon pile tester it gave a healthy 100A at
10.5V. Apparently thin wiring to the lighter outlet plus a decade of
terminal corrosion made the battery look worse than it really is. It's much
better connected directly than through the lighter outlet, and being tested
for Ah capacity.

You could check the condition of your wiring to see if excessive voltage
drop is increasing the appearance of low Amp-hour capacity.

A typical problem for mobility batteries is not being left on charge long
enough. 8 hours of sleep is too brief if you ran it down during the day. The
same batteries in a golf cart last longer because they have more time to
charge. Your Battery Tender appears to charge at 24V 2.5A, which gives 20Ah
in 8 hours and 30Ah in 12. The math isn't exact because lead batteries
charge inefficiently and draw less current as they near full charge. 2.5A is
a reasonably safe current if left connected for a long time, like a battery
maintainer, but not a fast charge.

https://www.mastervolt.com/charging-batteries/

I can't recommend any particular charger because I build my own, with volt
and amp meters so I can fast, slow or taper charge and manually correct for
battery type, temperature and condition. I made my 24V 20A charger from an
arc welder.

danny burstein

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Mar 26, 2022, 11:24:59 PMMar 26
to
In <t1obhi$e2j$1...@dont-email.me> "Jim Wilkins" <murat...@gmail.com> writes:

[snip]

>charge. Your Battery Tender appears to charge at 24V 2.5A, which gives 20Ah
>in 8 hours and 30Ah in 12.

I have the 3 amp, 12V, unit. This brand is reasonably "smart",
and basically pumps out (a nominal) 3 amps until it detects
the battery is almost charged, then [some smaller amount]
until 99%, then trickle charge to keep topped off.

A related issue is that... when the battery is dead, dead,
and the Battery Tender doesn't "see" enough voltage, it'll
refuse to send any charging current.

One hobby I had in my former area was going to [big facility]
auctions, where they were selling the UPS's for $5 or so.

About 3/4 of them were ok and only needing a battery swap.

And on about half of those... simply removing the old
battery and hooking it up to a "dumb" charger, so as to
bring it up to (a nominal) 10%, then got the UPS itself
to bring it back up to, say, 50% of factory new capacity.

Which is more than sufficient for plenty of my uses.



The math isn't exact because lead batteries
>charge inefficiently and draw less current as they near full charge. 2.5A is
>a reasonably safe current if left connected for a long time, like a battery
>maintainer, but not a fast charge.

>https://www.mastervolt.com/charging-batteries/

>I can't recommend any particular charger because I build my own, with volt
>and amp meters so I can fast, slow or taper charge and manually correct for
>battery type, temperature and condition. I made my 24V 20A charger from an
>arc welder.

Jim Wilkins

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Mar 27, 2022, 8:26:06 AMMar 27
to
"danny burstein" wrote in message news:t1ole9$6uf$1...@reader1.panix.com...

In <t1obhi$e2j$1...@dont-email.me> "Jim Wilkins" <murat...@gmail.com> writes:

[snip]

>charge. Your Battery Tender appears to charge at 24V 2.5A, which gives 20Ah
>in 8 hours and 30Ah in 12.

I have the 3 amp, 12V, unit. This brand is reasonably "smart",
and basically pumps out (a nominal) 3 amps until it detects
the battery is almost charged, then [some smaller amount]
until 99%, then trickle charge to keep topped off.

-----------------------

I like to KNOW what the charger and battery are doing, and this tells me:
tinyurl.com/v3bezz6b

In particular it shows if a battery has degraded enough that it rises to
full charge voltage at a low charge level. That's common with AGMs and it
fools a smart charger.

Jim Wilkins

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Apr 5, 2022, 7:32:08 AMApr 5
to
"danny burstein" wrote in message news:t1ole9$6uf$1...@reader1.panix.com...

One hobby I had in my former area was going to [big facility]
auctions, where they were selling the UPS's for $5 or so.

About 3/4 of them were ok and only needing a battery swap.

And on about half of those... simply removing the old
battery and hooking it up to a "dumb" charger, so as to
bring it up to (a nominal) 10%, then got the UPS itself
to bring it back up to, say, 50% of factory new capacity.

Which is more than sufficient for plenty of my uses.

--------------------------------

My UPS's charge to the float voltage, ~13.6V, which will fully charge a
battery in a few days without making it gas, and is the highest voltage the
battery can be left at continuously. An indication of full charge is current
draw of 1% of capacity or less, for example 180mA for a 12V 18Ah AGM. The
steady-state float current may be greater for old batteries. I build digital
ammeters into chargers to show the progress of the charge and condition of
the battery, which voltage alone doesn't indicate.

https://www.power-sonic.com/blog/how-to-charge-a-lead-acid-battery/

Charging at the float voltage is safe but too slow for daily cycling. It's a
good way to extend the life of spare batteries. I got 15 years of use from a
vehicle battery by keeping it charged, and the >10 year old 12V 105A marine
batteries I'm testing right now still run my freezer for a day or more.

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