This has been a common feature for like ... idk, 20 years? I think even the 80s W214 had this option, although that used a separate burner system instead of batteries.
High end cars had that feature for years. Lower end ones used various block heaters / car heater boxes / webastos.
This has been a common feature for like ... idk, 20 years? I think even the 80s W214 had this option, although that used a separate burner system instead of batteries.