I’m considering buying an EV to replace my aging diesel. I live in a very cold country where temperatures regularly dip below -30C in the winter.
I understand that EVs lose range in cold temperatures and that they need heating to use and charge without damage.
My question is this: if I plan on not using my car for several weeks, can I leave it unplugged and/or tell it to stop managing the batteries’ temperature to save energy and not damage the batteries?
I’m okay with spending half a day preheating it when I plan on using it again regularly, but I don’t want it to draw current all the time for nothing when I’m away on long missions.
For some reason, I can’t seem to find out if it’s safe to keep a fully unpowered EV in the cold for a long time…
We should be specific. This would be the standard 12v battery at fault; the pack batteries aren’t used to start an EV, not from what I’ve ever seen. I’ve a VW ID.3 and we had our 12v battery replaced with a heavy-duty one under warranty because many modern cars and their telemetrics, subsystems, cabin heating, etc will drain the 12v starter battery over an extended period of just sitting. The 12v usually runs the cockpit - not your big battery. Your big battery will top the 12v off.
The pack battery can sit for weeks - you do need to make sure it’s about 50-60% charged, no more or less, or you can incure aging to the battery. I’ve spent 3 weeks away a few times and lost 3-5%, so roughly 1%-1.5% a week, and this is both in Dutch winter (-2C) and summer (20C). It’s also important to not have the car preheat needlessly, so if there’s a scheduled departure time in the system, turn them off for that period you’re away. THAT runs off the 12v battery and will drain both batteries quickly.
But this is also the same as it’s ever been for ICE cars too - I lived for a decade in Colorado and we’d have glow-plug and charger boxes near the parking so we could trickle-charge a battery or keep the engine oil from becoming sludge when starting.