Has a good battery ever exploded in a light?

I know this is an old topic but I’m curious - does anyone know of an incident where a good quality battery from a known good source has exploded without being mishandled?

Yes, lots of times. CPF has a whole subforum just for that, as do RC airplane forums and similar.

https://www.candlepowerforums.com/forums/smoke-and-fire-hot-cells-and-close-calls-the-da.107/

Damn… maybe I will go back to protected cells

You should read at least the titles of the threads. The majority is not related to flashlights. As long as you don’t short the cells there’s no benefit of using a protected cell.

The potential for manufacturing defects worries me a bit. Maybe there’s no real benefit but I think I’ll still to protected to ease my anxiety.

Most of my lights I are used with unprotected cells, apart from some specific ones such as Jetbeam RRT01 and 1 or 2 more (some that have stock protected cells, such as Olights or Wuben).

However, when I give a flashlight that uses Li-Ion cells to someone (parents, aunts), I always pick protected cells for them. I know they don’t have the know-how and don’t pay so much attention to charging/discharging so I try to give them protected ones.

Some threads are also about lithium primary cells which I think are worse than li-ion in term of safety.

Is that not just a false make believe sense of security? Maybe I am confused by your meaning?

There are reports of manufacturing defects causing battery explosions. It may be unlikely, but it being possible is worrying.

The only issue I ever had with a Li-Ion cell was due to my mistake. I accidentally put a reversed cell in a flashlight that didn’t have reverse polarity protetection (I didn’t know that) and it got hot. Ony issue in 5 years using Li-Ion cells, and it was my mistake.

As long as you are used to
a) charge those cells correctly,
b) use them properly in your flashlights,
c) store them adequately,
d) not “shorting” them, and
e) buying them from reliable sources,
I would say that you won’t have issues with those unprotected cells.

Sh!t may always happen, but it is not that common.

This topic is way overblown (pun intended). Use common sense and take advantage of the volumes of safety information available about rechargeable li-ion cells and odds of ever having an issue are slim to none.

Exactly what does the protected part of a protected cell protect against?

Don wrote:

"But as I said long ago, you are more likely to be killed by a dead fish dropped by a seagull in the Sahara Desert than by a lithium ion"

According to Fenix:

- undercharging (appreciate most lights protect against this)

- overcharging (most chargers would protect against this)

- overheating

  • short circuiting due to impact or mishandling near the positive terminal

I got into 18650 Lithium-ion batteries 15 years ago. Had lots of counterfeit batteries; recycled sold as new, fake labels up to 10,000 mah 18650’s. Garbage chargers that time charged. I received two that where CR123A’s inside 18650 bodies. I’ve gotten protected cells that only had a plastic disk instead of a PCB. That’s gone away or really slowed down now. True issues now are mix matched cells in multi cell lights. Some better ways to manage the risk. Real batteries made by quality manufacturers. Single cell lights, matching cells in multi cell lights, using the right battery, quality charger. PCB’s are a good idea in multi cell lights especially those in series.

Unless that ion is going at 0.99c, in which case all bets are off.

Never had a battery explode.

But I did have a scare a few months ago with a barely used Vapcell H10 purchased with an FWAA.

While I was holding a light with the cell installed I noticed it was very hot even though the light was not on. I opened it up and pulled out the cell and noticed the cell was extremely hot. So much so that the shrink ramp had pulled itself over the can like a sock shrinking. Probably 1/3 of the can was exposed.

Even after taking the cell out of the light it remained really hot for almost an hour. Then it cooled down to room temperature. Checking the voltage revealed the cell was dead.

The next day I took a look at the cell again and noticed a clear liquid had come up through the can and was pooling around the positive terminal. At that point I discarded the cell.

It appeared that when the cell shorted, the protective Circuit Interruption Disk (CID) had popped up disabling the cell and preventing an explosion. It’s bad that the cell was defective, but good that the CID functioned as designed to disable the cell and prevent catastrophe.

This is the first time I’ve ever had a CID trigger in a cell, and it was nice to know the system worked. I think the short was internal to the cell and not the light, since other cells continue to work in that light with no issue.

I did not seek a refund for the cell, since I had actually received an extra H10 I hadn’t ordered. This malfunction just got rid of the extra.

I’ve never encountered a 18650 battery “exploding”. The worst I’ve ever seen was one in the process of “leaking”. It made a tiny fizzing sound while doing so, and those were pulled from old power tool 1.5ah or 2.0ah battery packs, those cells are run hard throughout their life… 2nd worst was the Sanyo 18650 “heater” batteries pulled from laptops. They still worked but always got very warm when charging over 4.0 - 4.1v.

I did have a pair of ’123s melt inside my MH20 once. Light was definitely off, but hot. Wtf?? Opened it up, both ’123s were scorching to the point the wrap split, leaving half-nekkid cells inside.

Nfi how/why that happened, not even what happened. Short, then heat that split the wrap, or a split wrap, short, then heat?

We may never know.

Yikes!

Years past, I recall reading multiple reports on CPF of lights using 2x CR123s exploding. I read that if one cell runs down slightly faster than the other one, the cell with charge will then end up reverse-charging the depleted cell.

The depleted cell then immediately vents a large quantity of oxygen and heat… and your light explodes.

This is why I don’t like using cells in series. Though there is still some risk, single-cell lights are inherently safer than running multiple cells in series.