Batteries technologie


Joined Nov 6, 2012
Car Batteries (Lead-Acid) will still function just fine at 120C,
but may require substantially increased Distilled Water Checking/Filling Maintenance Schedule,
and must be Charged at a lower Voltage because of internal heat generation, and Chemistry changes,
( 13.6 Charging Volts Max. @ 120C Continuously ).

This only works if you keep them in a fairly high state of Charge while they are being subjected to high temps.

When a Lead-Acid Battery is run dead, the Acid partially turns into plain Water, which will "boil-off" @ 120C.

The Acid in a Fully-Charged Lead-Acid Battery will not "boil-off" @ 120C, as long as it remains Fully-Charged.

I learned about this when I used to maintain a fleet of 20 Stretch-Limousines in Miami, Florida,
during the 98F degree Summer Days, Idling for hours with 3-AC Units running continuously.
The Dual Batteries were failing routinely, until I installed massively oversized Alternators (175A) and
then manually adjusted the Charging Voltage DOWN to 13.8 Volts with custom Voltage Regulators.
This completely eliminated all my Battery problems.
The Under-Hood Temps were averaging 220F degrees for as much as 10 hours per day.
The Air coming off of the Radiator Fan would literally burn your bare skin and cause Blisters.


Joined Dec 29, 2008
... Another type to consider ... said to be tolerant of high temperature. It may require a custom charging/maintenance system. ... Something about a minimum discharge voltage threshold.:
LiFePO4 Battery

Thread Starter


Joined Dec 22, 2020
I have a system that works in a temperature up to 125 ° C, I chose my components in such a way the system supports the 125 ° C, but I stuck in the choice of battery because it is a very sensitive element there is a risk of explosion