CR123A vs. hot AZ sun....


Dec 4, 2007
California Republic
So what types of cells WON"T explode and are safe to keep in a hot car?

Your best bet would be Energizer Lithiums, since they can survive the same temperature range and have the same shelf life as 123s, but without the "failure event" issues. Not cheap, but they're the best odds of working when you need them, and you only have to replace them once in a great while..


Nov 24, 2005
Phoenix, AZ
Hi Drivie,

I live in Phoenix. I have found primary lithium battery solutions work well. If possible, I would stick to 1 cell lithiums for primary 123s if that is feasible. That would, of course, rule out the G2. You might go to multiple lithium AAs, but I recall reports of exploding Princeton Tec PT-40s loaded with lithium AAs in a car in an earlier thread from a few years back.

:cool:If you carry a cooler with you on a regular basis during the summer, loaded with ice or blue ice, you could put flashlights and batteries in the cooler; just enclose in a plastic container. You just have to reload the ice every morning. This is a pain unless you do this for other reasons on a regular basis. I like the suggestion of replacing the batteries annually that was [referenced in a recent thread], at the end of the heat season -- October, perhaps:devil:.


Jan 19, 2003
Bellingham WA
Hello Drivie,

I believe the actual ignition temperature for CR123 cells is slightly above 450 F. If your truck gets that hot, you have one really hot truck... :)



Flashlight Enthusiast
Apr 7, 2004
Lost In Space
what i always like to point out in a discussion like this is:
What about the rest of the things in the car?
the cd/dvd players laser , it doesnt like to be that hot.
the plastic on the dash
even the power transisters for the stereo, and lots of other things like other electronics in the car.
while you probably dont drive it with a constant 140* , starting all that stuff up in the 140, then using it cant be good for it anyways.
got a cell phone?? a GPS ? most of thise devices also use a lithium type of battery (li-ion).

now whats the car cost? 6-40K itself, so why not treat the WHOLE kit and kabootle to a nice set of sun shades, mabey a cracked window (depending on the safety of that) or even a solar air moving fan.
these fully reflective sun shades, can send hundreds of "watts" of heat back out of the car , roll down shades can be modded with full reflective mylar, and windows other than the front ones, can have highly reflective (not dark that dont work) window tint film added to them.

so while your probably good to go with it under the seat, and not Charging in that kind of heat, think about your whole investment, and yourself, and the POWER needed to re-cool the car. that AC-unit runs on (not so cheap) gas. Do the whole thing, save money worry, and breakdowns and problems of everything.

they even have silver reflective car Covers (for the whole car) if you want to go for the full shaded reflected back effect, that is a bit overkill, but there is something for everyone in the land of sending the sun back away.
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Flashlight Enthusiast
Jun 16, 2007
they wont explode in your car alone (well not likely), but if the cells are of different capacitys from being in the car, then there is a higher chance of it blowing up. if you cant park in the shade, try the under the set method, shouldnt get above 140 down there.

I wonder how hot it is in the glove box?