[billnotgatez]

http://en.wikipedia.org/wiki/Electrolysis

Distilled water with a few drops of Sulfuric acid was a common method.

[P-man]

Yes, I thought the acids were good. You see, scientists at the nickel instittute have made a Rainey-nickel catalyst that is soooo muche cheaper and is just about as good with impurities as is platinum. If that catalyst is used inboth the fuel cell and electrolysis, the costs could be lowered greatly.