How's this for a crazy idea? Make a trailer that houses an ICE, gas tank, and generator that can charge the car while on the go? Sort of like a rail tender for electric cars. No need to haul around an ICE engine all the time, just on long road trips! One could even make it big enough to hold extra cargo, bikes on top, etc. Only question is would the generator be able to pump out enough electricity to overcome the extra weight and drag of the trailer? I'm sure the charging software would have to be modified to allow driving while charging too.