in a game its easy to change from fuel to battery :P
in my mind it just needs couple of mods..
instead of fuel % you have electric charge %
change physics so the car dont lose weight when that % goes down.
just make the car like 200kg heavier compensate for battries.
so the whole stint the weight remains the same just that the charge % goes down..
oh and have some whiney crappy electric noise instead lol