where's the kaboom?

Here kitty kitty. Bad kitty.

On first read i thought it had split the case, and i was gonna ask about what the innards looked like and how it was constructed, e.g. jelly roll around a mandrel or flat layers of a rectangular pack, etc.

but then i see that it was only the wrapper split, so the leakage was out the vent under the cap. Seems strange that it got so hot and over pressurized enough to vent during a total discharge. i wonder if there is a datasheet available for that cell to look at the chemistry.

The big Kaboom with fire usually occurs during a charging session after a deep over-discharge event, but sounds like you had a close-call and were lucky.

This was a good post for me as it acted as a reminder to have some serious respect for Lithium Ion batteries. I was going to suggest the alkaline battery cleanup with vinegar, but of course LiIon batts don’t leak a strong base like alkaline leakers thus your soap/water cleanup makes sense.
I found a few good links re: LiIon battery hazards and cleanup. I had one go south as in take off like a smoky rocket across my workshop one when trying to extract a 18650 batt from a vape pen, batt shorted I guess, scary shit.

I think taking batts out of non-rotation lights is sensible. This thinking makes lights with non-removable batts less appealing to me now.

Are most or all non-removable li-ion batteries protected cells? Might be a stupid question but I actually don’t know.

They don’t really go boom. They can spit a little fire if the can gets penetrated in some way. One little tiny cell in a flashlight isn’t going to be able to spit much fire. I think being in the flashlight is probably the safest place to keep them unless it’s a light with multiple cells. I would retrieve that from the trash and take it outside and look for dents in either end. Does that light have springs in both ends? It’s probably related to the fall in some way but was it a battery issue or did the flashlight do something to cause a quick short high drain?

Nope, it’s thoroughly waterproof, even from the inside. :laughing:

Seriously, battery tube from head was a chore to unscrew, so drizzled detergent down the hole and completely drownded it in hot water coming full blast from the faucet. Once I did unscrew it into 3 pieces, I was able to completely clean out everything.

No condensation under the glass, not a hint of fogging, nuttin’.

Dropped in a LFP cell (had it handy), and it still worked fine.

I had a pair of ’123s go all China Syndrome in my MH20 for some reason. Both wraps were split and crinkled, both cells down to almost 0V, but no leakage. Nfi how that happened.

Still chugging along, thankfully.

No, all li-ion are not protected, in fact none are from the factory to the best of my knowledge. The protection circuits are added post production and re-wrapped. All have intentional weak spots to reduce the violence of venting from the factory, so actual explosion is not what they do. normally. IMR, and INR chemistries are less volatile than the ICR that was used previously. Usually a battery venting might have fire but not an explosion. Inside a light there is less oxygen, so I am not surprised a tiny 14500 did not have flames. Had the same happened in a light containing 4x18650 cells it might be different. Had this been an ICR battery, it might have been the kaboom you speak of, but the stored energy of a 14500 is not going to be enough to be an extremely impressive kaboom. The fact that the cell vented without flames at all is fortunate even with IMR, and INR. You can easily see on the internet, videos of controlled intentional ventings by doing insane things like dead shorts or hitting them with hammers, with sometimes less than impressive results. That being said, even the INR and IMR can if venting cause flames. It can, if depleted too far, cause venting and flames if attempting to recharge. That is why most chargers, will refuse to recharge batteries that are too low in voltage. Some expensive re-chargers have special re-charge teqniques to recharge very depleted cells, but I would not risk it. I have had a house fire before, so I tend to take li-ion batteries and their potential dangers very serious, and do not push the envelope with their use. If a battery is too depleted to accept normal charging, I toss it. I do store some batteries in single cell devices with the tailcap loosened, but most I store in plastic boxes. None are stored long term in multicell devices. It is not that hard to remove them and put them in 2 cell plastic boxes for their storage. I have never seen or heard of a battery self depleting, and then venting due to low charge, and better li-ion batteries can hold their chages for years in storage…self depleting very slowly. Most violent venting events are due to the batteries mis-use or as in videos, intentional acts.

A lotta people have lights all over the place with cells in ’em: in drawers, in the garage, in the basement, scattered all over the place like they’re old plastic D-cells-and-hotwire-bulb flashlights, and if you forget the check on ’em, or forget about them completely, that’s exactly what can happen to them. Best case, the cells take a dump and ruin the light, but worse case?

I only keep cells in a haldful of lights, that those that are in daily use, and only a (very) few that go in’n’out of rotation. All of the latter, though, are tailcap-locked-out.

Long gone, no visible damage to the cell except for the split wrap and of course its spilled innards.

Au-coated spring on the tailcap and just a flat nubbin on the driver board.


(click me!)

shows the driver and profile of the tailcap.

Didn’t fall more’n like 8” and roll another 1’ or so the rest of the way.

My previous post missed the non-removable from your post, and I suspect that non-removable battery devices have protection circuits.

Had Tenergy 9v. NiMH melt inside a device last week. It was not the device’s fault. Put a new one in and works fine. What would cause it to melt is beyond me.

How old was the 14500 battery and where did you get it from? Seems strange that a small drop would cause the battery to leak. And when was the last time it was charged?

Glad it didn’t ruin your GT Micro (and perhaps your cat saved it)!

First shots fired in the War With The Machines?

EBL 14500s, April 2018 (looked it up), Amazon.

Can’t say it was a drop, as he knocks things over all the time. Either swinging his tail around, or rubbing his face on things. Nothing to purposely knock things over like you see some cats do.

Don’t recall when it was last charged. Blinked out 3.6V a few days before, which is about when I’d top it off When I’d Get Around To It.

I’m hoping so. I always keep ’em facing me (lit sideswitch) so I can see where they are in the dark, and it was fine one day, dark the next.

At least no kitties were hurt. When I was a kid, we had a cat that burned his lips off biting a lamp cord.

Maybe it was a bad battery? I’ve read that it’s risky to buy Li-ion batteries on Amazon and eBay.

Holy $hit, EXACT same thing happened to Max (13 YO and still with the living) Saw the idiot chewing an extension cord and it shorted in his mouth. Damn cat must’ve jumped 4 ft in the air. Not sure if his lips were burnt because I didn’t check. Hasn’t happened since…Stupid Max

Don’t think so, as I got a few “in service”, and they’re fine. All came pretty close to stated capacity.

Did get 1 dud out of 16 (2 orders × 8 cells), grexed, and their CS sent a whole new 8pak!

They seemed to be pretty good, all in all.