As i uderstand them, these Chrysler EV's are one drive line. They use an electric motor excliusively for motive power but have an onboard charging system.

The generator is a finely tuned unispeed motor that would be very efficient. The powerloss from gas to electric is equaled by the efficeincy of the generator system.

Basicaly the generator is luggage in the trunk when commuting to work coming on only when the 40 mile range of the battery is exhausted or the heat or AC is required. This concept would, I suppose reverse the MPG ratings so you would get something like 32 MPG highway and 100MPG city.
But, your houshold electric meter would melt.

The whole idea was described a while back in Popular Science mags during the Oil Embargo. They used a 20 HP turbine driven DC generator and a 25 HP electric motor. Just never seriously considered by the big Auto makers.

roadster with a stick