Interesting points
The use of fossil fuels in our civilizations stems directly from the sheer amount of energy they contain. I have always been convinced that, however we get to electric cars, we will never see electric construction vehicles - or planes, for that matter. Fossil fuel is a must when you need 500HP to lug twenty tons of rock around. Or else we've found Star Wars technology, in which case I accept defeat most graciously.
@Jimmy2Cows : after a bit of googling, I must admit that your point is unfortunately quite valid. Kind of puts to rest the entire notion for vehicular transport. Sad.
@Dwarf : the "greenness" of cars would anyways be impacted by the global aversion the human population has for nuclear power. It serves nothing to have electric vehicles if their recharging is done with coal plants. And nobody raises the issue of the toxic components of the batteries themselves.
That said, I doubt "charged" liquids would be any more of a hazard than the current incendiary liquids we use now. Plus, there would likely be less dangerous vapors to content with, so the refilling could be done in an airtight environment without much trouble.
Of course, the idea of plugging in your car and having nano-carbon batteries replenished in mere seconds would be nice, but then we're back at the high power grid connections issue we started with, and no change in the energy generation problem.
It seems to be a big mess in any case.