18650 bubbling from the inside

Hi guys. So I have a problem. While charging one of my red Sanyo 18650s, I noticed some bubbling noise from it, and noticed a small tear. In a panic, I took it out and I felt a nice oily scent in the air, and put it in sand.

Is it completely dead? And what might have been the source of the tear? Because it wasn't present when I tore down the laptop battery pack. That was the only cell that had the problem, as all other cells were completely fine, even charging and discharging the cells twice, but that one was bubbling in the 1st charging cycle. Thanks a lot!

Doesn't matter if it's "completely" dead or not. Throw it out in the yard immediately (or sand) and recycle. Do not attempt to reuse. If there's liquid coming out of it, there's obviously something wrong. Be safe

Just wanted to see what others thought. If I remember, it's a kind of solvent, as that smell is quite strange.

bucket of water ?

And if you want to make absolutely sure it's dead and doesn't start any kind of fires, hook up a 12V automotive bulb to it, let it run down. Then, take a nail and hammer through it. That'll keep anything from happening later.

BlueSwordM said:

Just wanted to see what others thought. If I remember, it's a kind of solvent, as that smell is quite strange.

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Yeah, don't breathe that stuff either... Lol. It is a very a unique smell. If you can get a picture of the tear/defect, I'd be curious to see what happened. You mentioned it was a Sanyo. Did it get really hot? Maybe it was starting to vent.

Nope, didnt get hot at all. At a charging current of 200mA, no cell got hot at all. Would be interesting. I'll take a picture once it's not dark anymore tomorrow. I'm not bringing it inside again lol.
The only diffenrence was a very small tear on the negative electrode of the cell next to the positive electrode. Probably an internal short created that tear, and let pressure out when charging.

Edit: Ok, Sanyo red 18650s from 2013 to 2016 are complete shit. Once they reach over 3.95V, they start dissipating heat, dropping its voltage constantly until it comes down to 3.95V, where the cell in completely fine, but I lose about 30% capacity and high IR(130 mOhms) isn't suited for my applications, even in a 5V powerbank, and that leaking Sanyo scared me.

Bin it for sure. Keep it in firesafe area.