20-01-2012, 11:43 AM
Fuel Cells
[attachment=16315]
The Promise of Fuel Cells
“A score of nonutility companies are well advanced toward developing a powerful chemical fuel cell, which could sit in some hidden closet of every home silently ticking off electric power.”
Parts of a Fuel Cell
Anode
Negative post of the fuel cell.
Conducts the electrons that are freed from the hydrogen molecules so that they can be used in an external circuit.
Etched channels disperse hydrogen gas over the surface of catalyst.
Cathode
Positive post of the fuel cell
Etched channels distribute oxygen to the surface of the catalyst.
Conducts electrons back from the external circuit to the catalyst
Recombine with the hydrogen ions and oxygen to form water.
Electrolyte
Proton exchange membrane.
Specially treated material, only conducts positively charged ions.
Membrane blocks electrons.
Catalyst
Special material that facilitates reaction of oxygen and hydrogen
Usually platinum powder very thinly coated onto carbon paper or cloth.
Rough & porous maximizes surface area exposed to hydrogen or oxygen
The platinum-coated side of the catalyst faces the PEM.