The temperature limits issues can be (in most cases) solved by simply putting the batteries underground. If you can go deep enough, temperature is almost const

The temperature limits issues can be (in most cases) solved by simply putting the batteries underground. If you can go deep enough, temperature is almost constant, check, as an example, Fig. 4 here: https://www.builditsolar.com/Projects/Cooling/EarthTemperatures.htm https://www.builditsolar.com/Projects/Cooling/EarthTemperatu...