
Same for the 'hybrids' like Prius...
The way forward at the moment is 'Extended Range Electrics'.
That is, electric cars which recharge through the grid overnight, and have a small secondary power source (gasoline/diesel or even hydrogen if you can get it compact and light enough) to PARTIALLY recharge the battery during travel.
Example:
(Numbers pulledo ut of the air, mostly)
The car can go 80miles on a recharge and if travelling at 40mph, it can travel for up to 2Hours until the battery runs dry.
Say the electric motor(s) pull 10KW on average...
(Not considering bouts of accelleration, or periods of regen braking)
You then have a 20KWH battery package.
You ALSO stick in a 5KW generator.
Assuming you drive normally for the entire trip, that generator will during those two hours generate 10KWH, enough for another hour's driving, and your range is suddenly 120miles... At the end of which you have another 5KWH, thanks to the generator... 140miles...
(Not bothering to work on smaller fractions)
That assumes, of course, that you don't stop anywhere, as the generator can run even when you have a pit-stop or a good meal.
If you don't need to drive that far, you may disable the generator and drive off of what's in the batteries, or just delay the start of the generator for a while.
At NO POINT is the car being driven by the generator alone. That way it can be made much smaller than what is used in cars today.
Cars also need to be made much lighter than they are today.
EX Electrics solve some of these problems as unlike the hybrids, they don't need to have conventional driveshafts/gearboxes and the engine is much smaller. (they can use 2/3/4 smaller electric motors mounted in the hubs to move the car, which also throws away the differential, which is not only heavy, but also a energy-loss)