Before you decide on any battery type , have a look at the temperatures I recorded today after my car had been in the sun for a couple of hours ... I double and treble checked the figures ... This was in the UK where we don't get ultra-high temperatures.
Keeping batteries in the car. (Posted earlier today , still waiting for any responses).
Today , I did some measurements of the temperatures inside the car with a temperature in the shade of 69.8F (21C).
The car was left in the sun with all the windows closed for just over two hours with the sun shining on the black dashboard top.
The temperatures were taken with an infrared thermometer which I know is accurate to within a couple of degrees at 100C.
The dashboard top measured 149.0F (65C).
A glasses case in the top of the glove-box measured 124.5F (51.4C).
A torch (Trustfire F20) in the bottom of the glove-box measured 111.5F (44.2C)
Bear in mind that the outside air temperature in the shade was only 69.8F (21C) ... The interior heats up way beyond what I thought I would measure.
On a hot day , say in the eighties , who knows what the temperatures would be.
As it is , the bottom of the glove-box is already near the maximum temperature quoted for Lithium cells ... I might have to put a storage bin under one of the front seats to keep a torch in , unless someone has a better hiding place that would be cooler ... It would be preferable to have the torches ready to hand rather than being kept in with the spare wheel under the boot floor.
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