Patent ID: 7338727

Claim:
A method of operating a fuel cell system comprising a plurality of fuel cells, each fuel cell comprising a fuel inlet for fuel, an anode having a catalyst associated therewith for producing cations from the fuel, a fuel manifold connected between the fuel inlet and the anode for distributing the fuel to the anode, an oxidant inlet means for supplying oxidant, a cathode having a catalyst associated therewith and connected to the oxidant inlet means for producing anions from the oxidant, said anions reacting with said cations to form water on said cathode and an ion exchange membrane disposed between the anode and the cathode, for facilitating migration of cations from the anode to the cathode, while isolating the fuel and oxidant from one another, the method comprising: (a) supplying one part of the fuel to the fuel inlet of the fuel cell for reaction at the anode to generate electrical power and heat; (b) providing a catalytic reactor for promoting reaction of the fuel and the oxidant, supplying another part of the fuel to the catalytic reactor and supplying the oxidant to the catalytic reactor in an amount greater than the stoichiometic amount required for the combustion of the other part of the fuel to ensure complete consumption of the other part of the fuel, and thereby to generate a flow of heated and humidified oxidant; and (c) supplying the heated and humidified oxidant to the oxidant inlet of the fuel cell system, for reaction at the cathode with the one part of the fuel to generate electricity and heat; and (d) supplying the oxidant and the other part of the fuel to the catalytic reactor, prior to supply thereof to the oxidant inlet.