Please help me figure out these lithium pouches

[Quinc]

I was recommended to come here from the modifiedelectricscooters forum. I am fairly new to EV and have only used SLA batteries until now.

I got these batteries to try out. I think they are for EV, they where bought from a liquidation sale and there is no info that came with them. I would like to use them on my sons mx 650 with industrial 3/4hp motor.

Anyway I am hoping the brilliant minds here can help me figure out what these are.

Specs:
-Each pouch is 1.38v - 1.48v (Not sure how many years since last charge)
-Weigh around 250 grams each

Question:
-How many aH do they have? Is it possible to get an idea by weight or size?

-Anyway to figure out the discharge rating?

-Any tips for how to crimp them? The place I got them from had some that appeared to be folded over and crimped. For the test run I was able to bend and crimp them with some female spade connectors.

-Lastly would the IMAX B6 charger be a good charger for these or would I be better off with something else? Also would I be able to charge them at 12v or would I have to charge each individual pack?

Here is a 10 pack I put together for 13.xx volts and hooked up to a razor 350w motor. Watch how much the voltage drops with no load. Hoping they just need to be charged..
https://www.youtube.com/watch?v=I5Fbp8Y6Jjo

 

[Hwy89]

I can't be of much help identifying your pouch cells but I hope you didn't pay much for them.
Lithium cells that have dropped below 2 volts for any period of time are not likely to recover. That 10 S pack you put together should have been between 30 and 40 volts not 13 volts. Those cells are so far below the shoulder of the discharge curve that there is practically no energy left in them.
As an experiment you might take a couple of individual cells and try charging them up on an RC balance charger using the 1s life setting. If you can get them up to 3.5 volts stop the charge and let them rest for a few days. Measure the voltage periodically and see how much self discharge there is. You should do this outdoors in a flame proof enclosure.
Report back if you can get a few of the cells to pass this test.

 

[999zip999]

We need a little help are they lipo 3.5v normal charged to 4.2 volt. Are they lifepo4 3.2volt normal charged to 3.6 volt ? Chemistry matters.

 

[pa.hioficr]

I'm with Hwy, those are lower end and capacity pouches for sure but identifying them is next to impossible. I've revived packs which went below 2v but they never return to above 92-93% capacity and the voltage drop under load says to me that they are either very low C rate (2-3) and of low capacity to begin with or just damaged.

One method of testing would be using a charger which can measure their internal resistance, it could be a failed cell or two taking down the 10S pack you built (dropping very low very fast under any load) i have some old 8AH pouch cells in 6S configuration which each have at least one bad cell where the IR on most is between 8 and 13 the bad cells are between 25 and 34 and simply must be removed from the packs - then I could in theory build up a 10S 8AH and likely get 7AH solid out of the remainer but 10S is useless to me for all my applications (I have nothing which runs on 36/37v nominal).

Sorry it's not better news but if it's only one bad cell which bottoms out to 3v or below under load you could just swap in a proper pouch without damage and have a working pack, still based on size I would say they can't be more than 3300 mah pack or 3.3 AH to begin with so if rated even for 10C you could only pull 33A continuous and it would have a signifigant volgate sag where as my 8AH are 30/40C so drawing 240A from perfect cells would be doable all day long and obviously at 10C or 80A they would be just fine. The lower the C rating the worse off the cells are and the wider the Internal Resistance (IR) is between series cells the more sag you will get.

Hope that helps to explain a bit further and gives you ideas for options.

-William

I hadn't even thought about Lipo vs LiFePo or LiFePo4 the latter 2 are always lower C rate with more SAG.

 

[Quinc]

Thank you for the replies!

Would the SKYRC iMAX B6AC V2 Dual Power Professional charger possibly put some life back into them? Or should I be looking at a different charger? Plan would be to run them at 36-44volts. But dang at only 3.3ah I would need to run 90 of them to get 20 minutes of use.


URL to charger:
http://www.amazon.com/Genuine-SKYRC-Power-6Amps-50Watts/dp/B00ND7J38C?ie=UTF8&psc=1&redirect=true&ref_=ox_sc_act_title_1&smid=A2KAJVTI3A83LE

 

[Hillhater]

Unless you can find some data /specifications for these, you are working in the dark not knowing what their nominal voltage should be. Charging damaged / over discharged cells is dangerous
Most chargers wont charge a Li cell that is below 2 volts for safety reasons.

 

[Quinc]

Dug through the boxes today at lunch and found a paper with a brand name and model. Only thing google comes back with is this site!

So comparing the weight of these pouches with the chart below I would say these are around 12aH (250 grams) * i do not see any that match the model number I have.

https://endless-sphere.com/forums/viewtopic.php?f=31&t=36280

 

[Hillhater]

Ok.. It does seem they could well be the Dow Kokam SLP 60205130 , 13Ahr power cells .
Very nice cells......if they were not so low on voltage !
But DK are (were) a very quality cell and may just survive a deep discharge. Certainly its worth a try .
If you have a charger ( or lab power supply) try a very low charge current (0.25A) to see if a cell can be revived to 3.8 - 4.0 volts. Take precautions, one cell only, 100% monitored, in a fire safe location ( barbeque ?)

Why dont you try contacting the guys at FFR trikes / Outriderusa , who originally handled those cells on that ES post ?

 

[Quinc]

Ok.. It does seem they could well be the Dow Kokam SLP 60205130 , 13Ahr power cells .
Very nice cells......if they were not so low on voltage !
But DK are (were) a very quality cell and may just survive a deep discharge. Certainly its worth a try .
If you have a charger ( or lab power supply) try a very low charge current (0.25A) to see if a cell can be revived to 3.8 - 4.0 volts. Take precautions, one cell only, 100% monitored, in a fire safe location ( barbeque ?)

Why dont you try contacting the guys at FFR trikes / Outriderusa , who originally handled those cells on that ES post ?

Will the IMAX B6 charger I linked above be a good charger to attempt to bring them back, or do you recommend something else?

You could fill the outside of a barn with what I dont know about lithium batteries.

I also sent outriderusa and ffr trikes an email!

 

[liveforphysics]

Treat pouch cells with extreme care not to dent them or fold them. Do not put uneven pressure on them, and never put pressure on the edges of the foils, only pressure through the stack.

 

[Hillhater]

]
Will the IMAX B6 charger I linked above be a good charger to attempt to bring them back, or do you recommend something else?
!

IMax will work, but personally i would go with an ICharger 206b or its cheaper clone the Turnigy Reaktor, either of which will give more charger power for bigger cells, and can log data for cell testing.

 

[dogman dan]

Since nobody else mentioned it, you might want to charge those cells in a safe place, like outside, till you sort out which ones will hold a charge, which ones don't puff up when charged, or even catch fire.

It IS risky to bring lithium batteries back from the dead. Charge them, choose only cells with no dings or puffing, and test for internal resistance. Then assemble your pack from the best cells in the lot.

Most likely, you will have to use a dumb charger, such as a cell phone wall wart to bring each cell up to a voltage where the RC charger can start charging them. There is a good reason for this, hence my warnings to not do it in a place it would be very awkward to have a fire.

You may very well have a safe to use pack out of this,,, I'm just saying be cautious about the testing phase of this project.

 

[Quinc]

Thank for the replies and new found fear of batteries! I will be sure and charge them outside on a pavement slab with the fire extinguisher near by.

Doing more reading last night and it looks like people have had luck charging them on the NiMH setting until the pack is above 3.2v then switch over to the lipo charger. So I will give that a try first. Then give my cellphone charger a shot. Would attempting to charge 3 packs together with my Lead Acid charger at 2amps/12volts be worth trying?

 

[wesnewell]

Most 12V battery chargers charge at 14-15V, so charge 4 in series, not 3, if you decide to do this.

 

[motomech]

What dogman said, and...
You might want to rig up a lite bulb discharge tester like the guys who sort thru used lap top cells use.
There are threads here about this, try search words "used laptop cells".
Very time consuming process though and new Lipo is so inexpensive these days.
Guess it depends what your time is worth.

 

[Hillhater]

Since nobody else mentioned it, you might want to charge those cells in a safe place, like outside, till you sort out which ones will hold a charge, which ones don't puff up when charged, or even catch fire.
,,, I'm just saying be cautious about the testing phase of this project.

....what worries me is,...
...even when you do take the trouble to post safety warnings, ...it seems some folks dont notice / read it ! :lol: :lol:

try a very low charge current (0.25A) to see if a cell can be revived to 3.8 - 4.0 volts. Take precautions, one cell only, 100% monitored, in a fire safe location ( barbeque ?)

 

[dogman dan]

Looks like he did get the message.

Chances are they will charge safely, but you can just mentally picture it happening on a dining table like mine, buried in a weeks worth of newspapers.

If they test out ok, have low enough internal resistance, I'd use them. If they have high resistance and get hot when discharging at 1c rates, forget using them.

 

[Quinc]

Doing more research I came across a post saying that some companies store and ship the lipos at a very low charge and you have to "wake" them up. It sounds good, but I only read it in the one place.

I bought the imax b6 pro charger that I can plug into my laptop for more cell data. I will keep you posted on the results and if my house is still standing.

 

[999zip999]

Hard to watch cells charge it seems as soon as you walk away things happen.

 

[Quinc]

Charged her up last night from 1.48 to 2.05v on the nimh setting. @ .3amps only took 150ish minutes.. Good news is this morning the pack still shows 2.05v. So going to try and charge her the rest of the way today after work.

Would there be any issues raising the amps to .4 or .5 to speed things up or should I stay at .3?

 

[999zip999]

Like said slow to 3.5v as 3.0v is about empty. Will they hold 3.5volt. Then.
Where do you live ?

 

[Quinc]

Like said slow to 3.5v as 3.0v is about empty. Will they hold 3.5volt. Then.
Where do you live ?

I will toss it back on the charger when I get home and see if she will make it to 3.5.

Northern California above Sacramento.

 

[Quinc]

Is it normal for the battery to take this long to charge? Going from 2.05v to 2.17v has taken roughly 4.5 hours @.3 -.5amps.

 

[Chalo]

[...]picture it happening on a dining table like mine, buried in a weeks worth of newspapers.

Newspapers? Like, physical newspapers, made out of wood pulp and chemicals? Did you get them at a vintage store?

 

[Hillhater]

Is it normal for the battery to take this long to charge? Going from 2.05v to 2.17v has taken roughly 4.5 hours @.3 -.5amps.

What "pack" configuration are you charging now ?
4 cells in series ? Or 4 in parallel, or just a single cell ?
Either way though, that 0.3 amps for 4 hrs is only 1+ Ahr into a 13 Ahr cell, so dont expect the voltage to move fast.