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Swollen LiFePo4

Daniele

New Member
Joined
Aug 23, 2020
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Hi everyone, this is my first post, :)
sorry but my English is not my native language. ?
I am writing to you for an opinion on a problem I have noticed.
I bought a battery pack like this:
after a few days that I got there, the cells swelled!
I charged them and let them stand for 1 day, each cell was about 3.5v, with a storage temperature of about 95/100F.
I contacted the seller for explanations, but he replied that this is not a problem.
What do you think about it?
thanks to anyone give me an opinion about
 

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Just found out I have the same problem. New set of 8 LiFePo4 batteries. One cell is swollen. Is there anything to do besides just replace?

Voltage reads 3.1VDC
 

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If the "puffing" is light (I mean not buldging) you can lay the cell flat, place something flat on it and put a few books, wait a bit, add a few more (gradual weight slowly and NOT too much, 5 lbs / 2-1/2 kg or something... If severely bloated or leaking in any way, then do not attempt & just replace.

I have done this with some "lightly" puffed cells with no ill effect, although I went to 10lbs. (5kg), over a few hours, a bit at a time.

Most manufacturers recommend "binding" the cells into a block with some low pressure. Refer to the cell manufacturers' docs for such info.
 
Like @Steve_S said .. as long as the battery is electrically good -- (rises and falls in voltage with the others) then its fine .. a little bloating happens to many cells (unless they work out daily -- come on!! Now THATS funny)

But I am with Steve -- I normally compress my LiFePO4 packs lightly together -- sort of SPANX for batteries ... (another funny one) ....

Do NOT try to rush the flattening processes by stacking a 25 pound cinder block on it ... just start wiht about 5+ pounds and add 5 at a time every 4-5 hours and you will be fine ...

NOW if its start bulging like its pregnant -- or the voltage is ALL over the place ... walk it outside - then figure out how to dispose of it properly - like Walmart or some battery place -- NOT TRASH ...
 
thank you all for the replies, what i ask, being new, is there no assistance from the seller? if they swell from new do you have to dispose of them?
the circle in the center of the poles what is it for?
 
thank you all for the replies, what i ask, being new, is there no assistance from the seller? if they swell from new do you have to dispose of them?
the circle in the center of the poles what is it for?

I suspect that is dependent on the seller. It looks like you bought your battery from BLS on aliexpress. I do not know what assistance you want from the seller, but it is worth asking them.

the circle in the center of the poles what is it for?

That is a 'vent' / pressure relief if there is a serious problem.
 
I have (8) BLS 190Ah cells also and when they arrived they all had some swelling. I contacted BLS and their reply was:
"Your battery photo is normal 190ah. The photo just sent is normal. Did you test the battery capacity? Your cells are very normal, mainly confirm that you use BMS protection and balance, you don't need to worry. "

You can see the gap in the pictures. I did a top balance and a capacity test on both batteries and got 190Ah and still had 12.4 volts left on the packs. I raised the low voltage cut out to 12.4V. I think this will increase the life of the pack, maybe I'm wrong on that.

I'm using the overkill solar 120A BMS: https://overkillsolar.com/product/bms-120a-4s-lifepo4/
 

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Going from high elevation to low elevation, the battery should suck in, not bloat out, if it is that sensitive to elevation changes (or ambient pressure changes).
 
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