[Pontiac]

By expanding negatively charged electrode (cathode) and positively charged electrode areas, the team produced a new device that, while more compact than current designs, permits higher currents and supplies a larger area for heat dissipation.

More compact yet has a large surface area?

What will they think of next?

[gr8eman]

I think this has a lot to do with newly developed semi-conductor materials that allow for better conductivity, i.e. efficiency and power transfer.

[HiTech RedNeck]

Rough surfaces have more overall area than smooth surfaces do.