What causes the pressure? Gas coming of the electolyte.
What causes the gas? Too much current through the electrolyte, or xcharhgiong it past full, causing it instead of just conducting, to electrolyse - i.e. generate gases from whatever it is.
In the case of e.g.a lead acid battery, the water gets electrolysed to hydrogen and oxygen.
I am not sure what gases are prduced by LIPOS.
What the gas does is expand and puff and then pop the pack.
This is not in itself a p[roblem, but an expanded pack has lost electrolyte and put gas, instead of electrlyre, un contact wuith eth anodes and cathode.
Net effect is capacity and current handling is exremely reduced. Use that cell in a pack of otherwise un puffed cells, and its almost certain to over discharge, and over charge.
Then the pack will gas more, dry out, get hot and ultimately catch fire.
Then a safe failure mode (popped pack) becomes a LIPO fire.
Swollen paths are the first sign that a cell has gone bad. Use it and you risk the whole pack in flames.
According to Kokam, Kokam SLPB batteries will not explode even if punctured thru. They are made to gas out safely. Now, with that said, we go to the next dangerous phase. They will, if shorted, and having the right amount of resistance, heat up hot enough to catch fire, or catch surrounding items on fire.
I think if you charge them in a safe area, outside the aircraft, then place them back in, you will be just fine. Heck, the carriers ship them all over the place in plastic bags. (I'm not treating this lightly...if puffed...discard them)
Check Kokam here...
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