One more observation I have made is that the tendency to heat the battery seems to also be influenced by the level of charge in the HVB. When my FFE battery has more charge, like on the weekend when it has only been used to go to the store and back, the car is MORE likely to do the battery heating outside the VC window. Not sure why that is but it is what I have observed given roughly equivalent outside temperature and equivalent time the car has been sitting unplugged outside. Perhaps it is more 'stressful' on the battery if it gets cold at a higher charge level??
