“But there’s a problem there: “one good battery” in that context does not exist and cannot exist. It isn’t an engineering problem. It’s a physics problem.”

Actually I believe it will be a capacitor. Their characteristics are much better suited to vehicle use. There has also been less intensive development of capacitors than batteries to this point so there is more left to exploit.

I used the word battery because the average Joe uses that word for electricity storage device. This was a comment on a political blog post, not an engineering essay.

JFTR: The green power source I envision is the nuclear power plant.

Anyway, thanks for the negativity. Those who predict failure at the start and say I told you so as each problem is encountered have always been the ones who improved life for the rest of us. Where would the world be without guys like you?