Re: Cold Climate EVs
A technique I really like for especially cold weather is to water cool the batteries. Put them in a heavily insulated box, and run the same water through the engine and controller (this only works if you have at least the motor on water).
Insulate the crap out of everything, and then install a small radiator in the loop. The optimal coolant temperature is about 45C, so when it get to that temperature, you can start a fan blowing on the radiator (and putting some heat into the cabin!).
You will be getting 1kW+ of heat. Add in the heat from the batteries and you can actually have a reasonable temperature car (2-seater). If it is still too cold, you can always add a heater to the loop.
Make sure to run the cooling loop when you are charging them.