Canadian Consulting Engineer


Fuel Cells

The Ballard fuel cell converts hydrogen derived from fuels without combustion. At its core are two electrodes, the anode and the cathode, separated by a solid polymer membrane electrolyte. Each of the electrodes is coated on one side with a thin platinum catalyst layer. Hydrogen fuel dissociates into free electrons and protons (positive hydrogen ions) in the presence of the platinum catalyst at the node. The free electrons are conducted in the form of usable electric current through the external circuit. The protons migrate through the membrane electrolyte to the cathode. At the cathode, oxygen from air, electrons from the external circuit and protons combine to form pure water and heat. Increasing the number of cells in a stack increases the voltage, while increasing the surface area of the cells increases the current.Flow field plateHydrogenMembrane electrode assemblyAirExpanded single fuel cellCompleted fuel cell stack