Maybe I'm not very creative or I don't have the ability to expand my horizons, but I don't really see EV's getting the same type of mileage as gas cars. Finding a battery that has 10 times the energy density of lithium will bring about a new problem: getting the energy in there. One of the beauties of the electric car is being able to charge at home. I really don't like the Leaf requiring a special outlet. I think it should plug into any outlet. If you start getting into some really monster sized energy density packs, you'll be REQUIRED to look for charging stations that could pump that many electrons into your tank in a reasonable amount of time, as it would need to deliver a serious amount of amperage that most household circuits can't handle. It seems electrics from OEM's can do 100 miles already, which is well over 3 times what the average American drives per day anyway....
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