li -ion for a vehicle light?

Well I got a new truck that has a huge center console and I would like to build a light that will mainly stay in my truck. I know li-ions dont like extreme temperatures but any opinions are appreciated.
What type of battery would be suitable for a vehicle light?

my test of a light in the van center cupholder using a kingkong 26650 has shown no degradation in 2 years.
the paint on the ultrafire light didnt fare as well and i painted it.it had faded to a golden brown where the sun hit it.
but the cell that stays mostly full has done well.
has about 30 cycles on it.after 10 cycles it gained a bit!
btw i like your sig!

It’s not just that, check his “location”. It appears that the irony is not lost on Solar. :slight_smile:

I don’t know about degradation, but I had a light with an 18650 in my car this last winter. It didn’t take any permanent damage, but it refused to turn on if the temps were below 25-30. So now I also have a couple lights with energizer lithium AA’s that I know i can rely on in an emergency.

And even if you live somewhere warmer, I don’t think I’d personally be comfortable leaving a li-on in a car with ambient temps regularly over 100f

Mine did fine down to –15f
that’s the coldest we got so far.
I didn’t measure the actual temp in the van but being a conversion it has more insulation than most.
might have been a few degrees warmer inside.
btw if it fires up the led will warm it up and improve the runtime as it runs

LiFePO4 batteries may be an option. They tend to have lower capacity and a slightly lower voltage compared to 3.7 volt Li-Ion chemistries. But compared to 3.7V chemistries, they have better temperature tolerance when it comes to both cold and (especially) hot conditions.

No matter what you choose, you should keep it under the seat or behind it, there will be a difference in the temperature that it will be exposed to.

I like to keep my lights, batteries and car chargers, and other electronics, in a small soft sided lunch cooler, and in the trunk, in a truck I would keep it behind the seat, away from the hottest areas. I also prefer AA and AAA lights for the car, you can use lithium batteries if you need, and they are more common, even a passerby might give you a couple if you are working on your car.

That is some solid reasoning on the battery format, and the idea for the lunch cooler is great! Also on many newer vehicles, under the passenger and driver seats there may be vents for the Air Conditioning, they will cool things back down pretty quick if you have the lights there.

That’s for the replies and ideas. I really don’t want to keep 18650s in a hot car. It looks like I’ll have to research some AA light mods And stock up on some eneloops.

The laws and taxes here in Connecticut really are becoming oppressive. I can’t wait until I am able to relocate.