This is a cell I have been playing around with and it shows promise. I am making another cell that uses a 12in. disk that is mounted vertical in a thin container (2in x 7in x 13in case).  The case is 7in tall and the disk, which is is mounted to a shaft and can spin freely. Half of the disk is exposed above the case and the half that is submerged is in koh and a solid zinc plate (6in x 12in) sets about 1/2 in. away from the disk. Current is collected at the shaft and a piece of felt soaked in copper acetate was mounted so that it applies acetate to the upper half of the disk as it spins. The disk spins very freely. I spun the disk by hand very slowly and a short circuit test showed 6 amps a little faster and it went past ten. This way the acetate does not come into contact with the electrolyte and the zinc and does not dillute. I need to perfect the acetate application sytem and a low power motor could easily turn it. Zinc plated steel did not work well, it disolved very quickly. You have to use solid zinc.

http://www.youtube.com/watch?v=eQBlJGLWYRA

It is zinc plated steel..... I use it to test with. The layer of zinc is very thin. If you use solid zinc it would last a very long time.

Jesus

A 1/16 inch thick zinc plate is 300 times thicker than the zinc coating. 2hours x 300= 600hours.