18650's for car light?

I was wondering how many of you guys keep 18650 lights in the car? Is it a safety risk?

the capacity gets reduced if kept at high temperatures, i use eneloops for my car light

My jetbeam bc40 is always in my car.

I keep a pack with all my gear for SAR in my truck, and that includes a cheap ultrafire c8 and a few spare 18650s for it. I usually leave my windows open far enough for it to stay cool, but not lower than the rain gaurds, and use a pair of shades in the windshield that keeps it pretty reasonable even in the hot New Mexico summers. I usually have it pretty deep in the pack, and that seems to help keep them cooler than stuff laying out in the open.
I’ve been using laptops with lithium cells for a pretty long time and I’ve never had any problems with them in the heat, so I’m willing to take the same risk with my lights. I’d rather lose some capacity than be caught without a powerful light when I need it.

If you are still concerned about lithium cells in the heat you could always keep them in something insulated or just use some other sort of battries in your lights.

I use 2x CR123 in the light that lives in the car.

In the summer time, I don't. Mostly, I am concerned about drastically reducing the life of the cells.

So i guess as long as it is not hot out, I’ll go ahead and use 18650s for my car light. Don’t have a good sized AA light that is powerful enough.

Lithium + sk68 clone (3 mode)

I can not even tell you the brand name[if it has it!] of the Flashlight I keep in the glove compartment!

It was one of the first lights I bought. It takes 1/18650. I put it in there towards the end of August. I did think of the heat and what could happen to the battery. I am sure there were about a dozen or so days where the heat was probably 120 F. or more inside my car.

Next year I think I will come up with a way to protect it more since it will be in there for an entire summer!

The solution is just to keep an EDC on my hip! I am not going to remember to do that all the time and really do not want to!


I have to prepare for break downs and sleeping in the car on long trips, and aside from my edc I keep my headlamp and extra lighting and batteries in a soft sided lunch cooler in the trunk.

Since I have to deal with desert temps I keep mine in the soft sided cooler, inside of a medium sized hard shell cooler, with a gallon of water (inside of a freezer bag in case of bursting) in it for drinking and as a heat sink.

I hope that leads to the results that I desire.

You could just keep an LD01 on your key chain, it goes from 72 ansi lumens to a 27 hour run time at 3 lumens, and with a middle setting of 26 ansi lumens for 3 hours.

That is a full duty flashlight yet in a AAA key chain size, it is better than what we used to carry in the car and keep in our homes, yet sufficient run time for a night stuck in the car or on an elevator.