If you have a garage, your best bet is a battery tender, which keeps the battery charged overnight and warm enough not to freeze.
A lot of people also use engine block heaters. There's different types and they all work a bit differently. Usually you would start the engine warmer a few hours before you use the car instead of overnight.
A lot of people also use engine block heaters. There's different types and they all work a bit differently. Usually you would start the engine warmer a few hours before you use the car instead of overnight.