Lithium-ion battery safety 101

How do you know those were loose cells? The title just says “Teachers E-Cigarette Explodes”
That would actually be way worse if they were properly installed in e-cig.

This really helps. Thank!

Nice thread. :+1:

Well I think I’ve discovered the answer to whether it’s safe to keep LiIon cells in a light in your car during the summer heat.

My old car just burned up tonight and in the center console was a Convoy C8 stuffed with an Efest 18650. The interior was totally engulfed in flames for about 8 minutes before the C8 went “pop” and flew out the open door onto the ground in a shower of bright white sparks which lasted about 5 seconds before subsiding. Just then the fire crew showed up and began doing what they could but of course by then the car was history.

The interior of the car was at least a couple hundred degrees+ for at least 6 minutes+ conservatively estimating before thermal runaway occurred. The light was in the closed center console which might have reduced it’s temps somewhat but given all that I saw tonight, I no longer have safety concerns for LiIon cells inside a light in my cars during summer’s heat. I’m sure it degrades the cells somewhat but I’m OK with that as long as they don’t self-ignite.

The fire started under the hood and I knocked it down 4-5 times before my extinguisher ran out. On the 3rd or 4th re-start I had the presence of mind to disconnect the car battery but something else was causing the re-ignition and I just didn’t have enough resources to win the battle. I quickly emptied the tool box etc from the trunk and was going for the dashcam and Convoy but the fire had gotten past the firewall at that point so no joy- time t stand back and watch. The cause of the fire was leaking power steering fluid which sprayed into something hot. It was at my nephew’s house and they have pics which I’ll add here later when I get them. The car was old with no fire coverage but I got my money’s worth from using it for 10 years so no great loss and I still have the work van and I’m OK so life goes on and I’ll get another car soon enough.

Phil

I’m really sorry to hear that and sorry insurance won’t cover it. It sounds like the power steering leak must have been pretty severe and being sprayed at just the wrong angle. Lots of cars leak all kinds of fluids. To me it sounds like the fluid some how may have being sprayed or flung onto the headers or header depending on the engine size. And those run around 1000 degrees. I’d have a hard time believing the heads would be hot enough to ignite it to flame, smoke yes. Only thing hot enough would be the header (exhaust manifold connected directly to the block) that’s just my speculation.
Your in good spirits about it though, which is good it could have always been worse lucky you were able to get out and not suffer burns. I’d say the interior if engulfed in flames was much hotter then 200 degrees. Flame is much higher, and a regular car fire can char a person behind recognition to where dental records are needed. So I’d say it seems very safe for the lithium batteries if it took 8 minutes in a car fire to explode. There is another thread on here where a guy is trying to make them vent and explode and the cells won’t do it. He is using imr cells I believe. at least you got your tools, maybe dashcam and your life. A new c8 is cheap. Glad your ok and not in a critical burn unit somewhere. And kudos to you for carrying a fire extinguisher. I don’t know of anyone who does. I keep a couple gallons of mixed coolant with me. That’s about all the firefighting I’d have

Man! When you “smoke test” a flashlight…!!!

Thanks for “taking one for the team”! I too am glad you and your family are okay.

SawMaster’s story actually disturbs me a mite. I had similar circumstances in my car until recently, only the ride itself has never presented a fire hazard (I check with the mechanic often); the fire hazard came from a loaded 18650 light and a loose cell I had on the glovebox. We are talking about a cheapo “Police” next-mode-memory reverse clicky garbage… with these puppies:

I’d forgotten those things even existed, as I had them since mid-2013, before I even had the car and a good while before I went fully knowledgeable flashaholic.

No kidding, these were sitting in there for at least a year, thankfully in a nook with no chance of moving or jostling around. I pulled them out of there this week, and tested the voltage on both. To my surprise, the blue one was at 3.9v; the yellow one with the absurd capacity, to no surprise, had drained to 3.3 volts. I carefully set them to charge on my Thrunite MCC-2 (the only charger I have that shows the voltage), and they took charge normally until they topped at 4.19v (yellow one got there a good bit faster, though).

I’m definitely gonna toss the yellow one, but the other I’m not quite as sure what to do with. I’m too impressed with its durability to go just one route. Any insight from my pals here?

Check this topic!

Kind or a relief he did not manage to get them to vent too easy.

I see nothing relevant to what I can/should do with the blue cell, Miller. Could you please make it a bit clearer?

No the relevance is to the part before your question.

But to answer just use it if it has enough mAh :wink: (I use some non good brands with low mAh in some lights I rarely if ever use but want to have ready anyway)
If you feel not 100% sure if it is safe, just dispose of it :wink:

Oh yeah, that’s just my case. I have a somewhat defective Olight S30 (high and turbo flicker wildly, but moonlight, low and medium all work fine) that I’m leaving at home for general utility, mostly for my mother’s convenience. It doesn’t need a burly battery, just one that won’t go BOOM.

basic lil’ bump

That cell seems OK for low-drain applications. But IMHO, muggles should not be given LiIon’s simply because they will not understand ALL the safety protocols- to them, a battery is a battery and it can’t really hurt you. Techies and enthusiasts can understand why these are different and must be treated differently. I have just one family member who I’d trust with LiIon- I know the rest too well to chance harming them through their own, er, “lack of sensibility” :wink:

Phil

A really good post!

This though:
http://www.candlepowerforums.com/vb/showthread.php?141137-Inhaled-vapors…
is not about rechargeable Li-ion cells.
Li-ion cells don’t have hydrofluoric acid in them.
That ancient CPF thread is about a C123 primary cell.

Is it dangerous to use magnet for connecting flat top batteries in series?

for Jerommel:
https://www.google.com/search?q=lithium-ion+fire+fluorine

The concern is that the fluorine compounds produced in the flame of a li-ion fire are inhalation and skin hazards.

Interestingly, a while back, some tests done in an argon atmosphere (no external oxygen available) showed no HF produced.
This confused some people; no HF was produced because there was no combustion, no flame occurred, just venting, in the absence of any external oxygen at all.

If the magnet slips to the side and contacts the battery tube while staying in contact with the battery, you have a short circuit of the full capacity of one or more cells.

If the magnet is secured — fastened so it can’t slip sideways — as glued in the middle of a disk or ring of nonconductive material, that’s avoidable.

Here’s one for example: A little part from JAXMAN: 26650 battery connector

Thanks hank. Looks like jaxman connector is the best option atm.

Okay, thanks for addressing it.