Have you ever had a cell(s) explode or vent in an undesirable and unexpected way?

[uk_caver]

I have had the odd issue with NiMH cells due to internal or external shorts.
As Helmut said, external shorts aren't really a cell issue as such unless maybe if they lead to some seriously bad consequences, but the internal short is probably worth mentioning.

I'd made up a battery pack from 3x tagged 4/3A cells, nicely wrapped in self-amalgamating rubber tape, and was giving it either its first or second charge at a relatively low rate (~0.2C), with the pack some way from being fully charged, but some way from being empty - maybe 1/4 to 1/3 full, judging from the contents of the surviving cells.

I heard a pop (probably the rubber wrapping failing) followed by a hiss and a faint cloud of vapour/smoke started to form.
Being late at night (I was about to go to bed) I just disconnected the pack, which continued hissing, opened the window and threw it onto the lawn to cool down.
Next day, it was clear which the offending cell was - it was browned around the positive terminal, and the heatshrink at that end of the cell was wrinkled, and split in a couple of places, but it was also clear that there hadn't been any external short - the heatshrink under the positive tag was still perfectly intact.

Whatever happened seems likely to have happened when the cell wasn't fully charged, but also not just as it began to charge, so it seems like an intermittent or spontaneous short of some kind.

 

[Chrontius]

An alkaline (Energizer) C cell is doing this RIGHT NOW. I've stuck it in my (cast iron) bathtub, just in case. What should I do?

PS: It's hissing, squeaking, and faintly smoking.

Update: In a Ziplock to contain fumes.

Also had a 4x23a "B65" type pack for a Brinkmann Maxfire with obvious (in hindsight) deficiencies in construction; the pack ends weren't secured to the pack, the positive nipple shifted during charging or handling, and contacted the inside tube of the flashlight body. When powered on, the short circuit current immediately melted the switch and caused multiple cell failures. As a result, I couldn't turn off the current - but once the switch was thoroughly destroyed, it also allowed the switch contacts to shift away from the battery pack.

I then went on to use the light with a replacement tailcap and a Surefire B65 that had lost its positive nipple (reducing its length just enough to fit) for years, until the B65 would no longer take a charge.

 

[reppans]

Had a minor AA alkaline venting once. Was "battery vampire" testing with ramdom dead AA alkalines using a Quark AA^2 on moonlight. Guess one of the batts went so low due to mismatch capacity/voltages, it started charging in reverse. Heard a "POP", rubber tailcap ballooned out, and one of the batts had leaked inside the tube. Cleaned it up immediately, so no permanent damage. Lesson learned.

 

[Helmut.G]

I completely forgot about that when posting, I had a recharged alkaline emit lots of gasses and a bit of fluid this year.

 

[Monocrom]

None! And I hope it stays that way.

 

[mvyrmnd]

I had an 18350 vent after an issue with the switch in a light. It was in a drawer at the time, and the vent was minor, so I was unaware of it until a sat or two later when I unscrewed hte head of the light and it hissed like a soda can - and stank. It spent the next few hours outside ( then washed out) and the cell was disposed of accordingly.

 

[loquutis79]

As opposed to a desirable way....?

 

[spydie fanatic]

I just had a NiMH vent yesterday while in my flashlight. It was a brand new eneloop xx 2500 lsd I had purchased off of eBay for $6. I had just gotten 2 of them in the mail for my fenix LD20. The vent episode happened during the initial charge from the factory; I think for this to happen with eneloops is rare. I've been using eneloops for years and never had any problems. I had the light on medium and standing on a table in my room to illuminate the whole room. The light fell over and I went to pick it up, the rubber grommet was literally domed out and the light had more warmth to it than normal on medium mode. I knew NiMH weren't as bad as li-ion, but I still put it in a plastic bag and took it outside. I unscrewed the head off the light and let it set outside for a while. I'm just glad I caught it as soon as it happened, which I attribute to the light falling over from the gas doming out the rubber grommet over the clickie.

Guess maybe I'll win the lottery now?


Seller said today he was sending me two new xx's...got my fingers crossed this time!!