My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars - this is very important - so you don't have to carry the return fuel when you go there.
Yeah, well I think anyone who likes fast cars will love the Tesla. And it has fantastic handling by the way. I mean this car will crush a Porsche on the track, just crush it. So if you like fast cars, you'll love this car. And then oh, by the way, it happens to be electric and it's twice the efficiency of a Prius.
A battery by definition is a collection of cells. So the cell is a little can of chemicals. And the challenge is taking a very high-energy cell, and a large number of them, and combining them safely into a large battery.