The other posters seem to have the right skepticism and are correct in that this technology is a possible improvement in energy storage, not generation.
The one place where this new capacitor might be an improvement is acceleration/performance of the car. The batteries in an electric vehicle are a substantial fraction of the total weight, thus making acceleration and handling suffer. If the capacitor has higher energy density (that is, energy stored per weight) then you may be able to get equivalent distance and better performance out of an electric car with less weight in batteries.