Explain how carbon-nano tube batteries work

[XT]

Was watching an episode of Sci-Fi Science, and Dr. Michio Kaku was speculating on how to build a real light saber. Anyway, the power source he mentioned was a carbon-nano tube battery. Could anyone explain in simple terms how it would work and what the potential energy we could (theoretically) get out of something like that? I realize that the technology is purely speculative at this point, but he used it in his design so it must be at least theoretically possible.

-XT

[Squink]

I’d WAG that the ‘carbon-nano tube’ bit is a futuristic way of saying ‘electrodes with a very large surface area’.
You can get more current out of a large surface area than you can out of a small one.
Here’s a recent patent application in the area:

Abstract:
A method of forming battery electrodes with high specific surface and thin layers of active material is disclosed. The method enables low series resistance and high battery power.
Claims:

1. A battery electrode made from open-porous metal of at least 1000 square centimeters surface area per cubic centimeter volume with the surface layer chemically converted into a film or layer of active material prior to incorporation in a battery; the active material is an oxide, hydroxide, or a salt of the electrode metal

2. A battery electrode comprising open-porous metal sponge or open-porous metal structure comprising one or more elements in the active material of a battery and the metal surface layer being chemically converted to form an adherent film of active material…

Neatly arrayed and hooked up nano tubes could give a higher surface to volume ratio than a metallic sponge.