Hi all - my first post on this forum - I'm about to order an Outlander PHEV here in Spain, but I've been lurking on the forum for some time.
I couldn't resist jumping into this topic however since I work for the European Space Agency...
Regarding the batteries, we put heaters on our satellite batteries. If they don't get warmed up, then they can't hold a charge. When we get enough power from the solar panels (after hibernation for example) the first thing that is done is to start warming the batteries so we can start to accumulate some stored power. There are different batteries for different missions, but that's the general rule.
I don't think that the PHEV battery pack has a dedicated heater, only an air conditioning unit to cool the system. I also suspect that space-qualified batteries are a tad more expensive that the ones in the Outlander
Emmet