See: http://sci-toys.com/scitoys/scitoys/echem/fuel_cell/fuel_cell.html
I had no idea an ultraclean rechargeable battery could be done so simply! Supplies: <<- One foot of platinum coated nickel wire, or pure platinum wire. Since this is not a common household item, we carry platinum coated nickel wire in our catalog. - A popsickle stick or similar small piece of wood or plastic. - A 9 volt battery clip. - A 9 volt battery. - Some transparent sticky tape. - A glass of water. - A volt meter.>> H2 and O2 are produced by short electrolysis runs, after which the bubbles clinging to the electrodes are catalytically recombined by the electrode surface material (platinum) to generate electricity :) 1/ The article features nice "explanations" of how it works, but how does it _really_ work? In particular, in the generating (fuel cell) phase, they don't say what makes the positive hydrogen ions climb "uphill" from the negative electrode to the positive one, anyone can explain this miracle? ;-) 2/ It seems to me a much higher capacity (and perhaps even practical) rechargeable battery could be made by using a hydrogen absorbing/desorbing material e.g. Pd for the negative electrode, and by making gaseous oxygen available at the anode. Storing the latter is not required of course, O2 from the air is fine... maybe a floating support which would keep a grid or flat serpentine shaped positive electrode at the surface of the water or just below? Michel
