The first practical battery stack was invented by Volta in 1800. Since then very little progress has been made in making it a practical power source for a man carrying motor vehicle.
We long ago hit the wall on power/weight no mater what material we use for construction.
Until we get a breakthrough in low temp super-conductivity or archive a miracle in quantum mechanics, Battery powered cars will never have the range/speed/cost to be an all around practical automobile.
If Aviation and Electronics had developed at the pace of the battery, we would still be flying Wright Flyers, and talking through tin cans with string.
The GM "Volt" is a political car only and it has already archived it's goal. As for the Smart EV, IMO, It will be just a be another "roadable" golf cart. A2Jack.