I believe that in Teslas, the main battery pack is for motive power, while the vehicle's electrical system (including doors and windows) is powered from a stand

I believe that in Teslas, the main battery pack is for motive power, while the vehicle's electrical system (including doors and windows) is powered from a standard 12V car battery which is kept charged from the main battery pack. Thus egress would be the same as in any other vehicle in a crash/fire.