why does this battery look bloated?

[willbanks]

years ago as a  kid i had a PSP and it stopped turning on. back then i believed it was broken. now i think, i'm gonna try and fix it. turned out as a kid i had been plugging in the wrong rated wall adapter, and it didn't turn on because of a protection circuit on the battery.

which brings me to the battery. it looks like it ripped itself out of its housing and doesn't want to fit back into its case, no matter how hard i push. it looks like it enflated. i'm going to just buy a replacement battery to relive my kid days, but does anyone know why?

[stj]

the lithium-polymer battery's generate gas when they fail.

[jpanhalt]

A "puffed" LiPo has failed.  We put them in the middle of a field and do target practice.   Whatever you do, DO NOT try to charge it indoors on the kitchen table while you go to bed.   They have a nasty habit of exploding into fire.

John

[mdszy]

Yep. This is a failed lithium-polymer battery. It's probably not dangerous as is, but if you puncture it or try to charge it, it'll go up in a big explosive fireball, so don't! You'll need to dispose of it properly at a hazardous waste disposal facility, it's a really bad idea to just throw it in the trash.

[willbanks]

wow thanks for letting me know! is there anything i could do with the circuit board attached with it? or is it probably broken too?

[jeroen79]

is there anything i could do with the circuit board attached with it? or is it probably broken too?

It would depend what exactly is on it.
Assuming it has the charging and protection circuitry you could use it with a battery of the same chemistry and similar capacity.

[Lolucoca]

I guess you could salvage the board for the protection circuitry and reuse it but I would certainly not try to desolder it using a heat gun

[frozenfrogz]

A little OT, but the processes happening during the breakdown of a LiPO battery are actually very interesting and there are a lot of research articles on the topic.
In an early stage organic solvents used in the electrolyte release flammable hydrocarbon gasses (Ethane, Methane, Propane,...). However, no oxygen is released (as stated by some "guides on battery use" from RC toy vendors and the like). This is what leads to bloated/puffed cells and especially when additional heat comes into play due to charging, the gasses can be heated above their flashpoint. Since no free oxygen is present, the cell will not burn, but expand and finally catastrophically fail in "rapid disassembly" e.g. explode. Some cells are outfitted with special pressure relief valves for that matter.
In case of an internal short circuit (molten polymer separator due to high temperature, mechanical defect, ...), heat leads to the breakdown of the metal oxide cathode, releasing oxygen. That is, when the cell catches fire (mostly without explosion), because oxygen and hydrocarbon gasses undergo an exothermal reaction, leading to even more temperature build-up, melting/perforation of the outer plastic seal, more material breakdown, ... and the cell quickly burns up in a cloud of magic smoke.

This is the very, very simplified story as you can imagine
Chemically there is a lot of things going on and the variety of toxic gasses that can be released by a failing cell are stunning.

Thought some of you might like to get teased to read a little on the topic, because I always do.

Regards,
Frederik

[digsys]

I love the smell of HF (HydroFluoric Acid) in the morning !!

[Johncanfield]

When I have puffed LiPo's, I soak them in a strong salt/water solution to safely discharge them.

[The Soulman]

[Tom45]

On a piece of plywood next to a wooden fence? 

[Simon]

On a piece of plywood next to a wooden fence? 

Well cmon, it is photonicinduction you are talking about, that is high safety by his standards.

[stj]

i think "bigclive" has a video where he charges one, and then puts a nail through it!

[kohjb]

Firstly, I know this is an old topic, but the problem still exists today. I do understand and have seen the countless videos of the drastic puncturing of the batteries to cause them to ignite/explode. I also do understand that the gases emitted to cause the bloating are all toxic.

However, I would like to know if anyone has good (objective evidence) of what happens if you just nick the foil of the battery with a pin to allow the gases to release (outdoors, say)? Would this cause an ignition event as well? Any research papers anyone has seen reporting on this? I could only find reports where they do the penetration test with a nail, and measuring the gases released from those events (e.g. https://www.mdpi.com/2313-0105/2/1/5/pdf), but could not find any on the small scale (e.g. batteries that have a built in vent).

Some background: I've actually had a bloated battery in my Samsung tablet, and was trying to remove/replace it. Voltage was still good, but bloated enough to cause the tablet's case to be deformed. The battery was glued via double side tape to the bottom of the case. When I pulled on the battery to remove, I somehow ripped the foil. This released the gas (unintentionally), but I observed that the battery deflated to its original form, and voltage etc was fine. I've also seen some videos that do it (e.g. . though I think some videos are being removed due to safety concerns), but never the "science" behind it. After puncturing the bloated battery, he seals the hole again to prevent air/oxygen from entering it. I've also watched BigClive test a bloated battery (), which read a low voltage. He deconstructed the battery (which was discharged) and did a little experiment of pressing the seperated plates of the battery back together, and could see that the voltage went up from something like 2V to about 3+V.

Thanks in advance for any info!

[Simon]

Not a smart move as a first post to dig up something so old. It's what spammers do. I've just unbanned you having banned you out of automatic response to an always spammer behaviour.

[Gyro]

...
However, I would like to know if anyone has good (objective evidence) of what happens if you just nick the foil of the battery with a pin to allow the gases to release (outdoors, say)? Would this cause an ignition event as well? Any research papers anyone has seen reporting on this? I could only find reports where they do the penetration test with a nail, and measuring the gases released from those events ...

I have punctured to outer envelope with a pin - just once, to release the Lipo battery where tt was wedged so tightly that it wouldn't budge without lengthy dismantling. I did it in outside and it was a calculated risk (I was able to very quickly remove the cell as soon as it deflated). The gas released didn't combust and the cell didn't heat up - but that was on a sample size of one!

I would certainly never advocate re-sealing the cell and continuing to use it. The gas pressure will have damaged the internal construction of the cell (as you found, squeezing the plates back together changed the voltage). Once a cell is bulged, it is dangerous to use and is only suitable for safe disposal.

[rpiloverbd]

It's faulty. Do not use it.

https://dwaaoz.com.au/why-do-lipo-batteries-swell-up/

[Renate]

I've seen this a lot, but never as bad as the OP's photo.

You should keep your eye on your devices and as soon as you notice that the back is a bit convex or something doesn't fit, retire it.
Nowadays they glue the heck out of batteries, so be careful when removing.
If you want to turn your old tablet into a wall clock you'll probably want to save the BMS PCB.
It has the ID, thermistor, smart chip, whatever to make your device run. At least you might want to take measurements.

I've got 6 devices now that I still use, running on 4V power supplies.
(Car tablet, hot spot and 4 retired devices for testing/regression.)

[viperidae]

I would be concerned about letting oxygen into the cell if the foil is punctured. The chemicals in the cell will react with oxygen. Potentially in a violent way, at any point in the future.

[amyk]

I would be concerned about letting oxygen into the cell if the foil is punctured. The chemicals in the cell will react with oxygen. Potentially in a violent way, at any point in the future.

There is no metallic lithium in a lithium-ion cell. The only concern is the flammable electrolyte. So I would say that deflating them shouldn't cause any problem as long as you don't cause a short circuit. As always, you're on your own if you do this...

[Mechatrommer]

...
However, I would like to know if anyone has good (objective evidence) of what happens if you just nick the foil of the battery with a pin to allow the gases to release (outdoors, say)? Would this cause an ignition event as well? Any research papers anyone has seen reporting on this? I could only find reports where they do the penetration test with a nail, and measuring the gases released from those events ...

I have punctured to outer envelope with a pin - just once, to release the Lipo battery where tt was wedged so tightly that it wouldn't budge without lengthy dismantling. I did it in outside and it was a calculated risk (I was able to very quickly remove the cell as soon as it deflated). The gas released didn't combust and the cell didn't heat up - but that was on a sample size of one!

I would certainly never advocate re-sealing the cell and continuing to use it. The gas pressure will have damaged the internal construction of the cell (as you found, squeezing the plates back together changed the voltage). Once a cell is bulged, it is dangerous to use and is only suitable for safe disposal.

i have done it a few times. carefull not to poke the chemistry layers inside it since you wont be able to fix anything by doing that, more likely to make it worse. i wont bother to reseal as gas may develop again, so let it be free anytime after. anyway, inflated cells is a sign that its going to die pretty soon, so you may still use it a few times at degraded performance, you may wont. btw we dont talk this much esp when there are narrow minded politically correct homer in their cubicle having a bad days looking around to talk about safety. so this technique may only be usable/helpful to photo inductionist breed human type. ymmv.