Patent ID: 6645650
Filing Date: 2003-11-11
Classification: H01M,Y02E

Abstract:
In a procedure for shutting down a fuel cell system that is delivering power to a primary load, the system comprising a fuel cell having an anode electrode, a cathode electrode, and an electrolyte disposed therebetween, said cell also including an anode flow field for carrying a hydrogen containing fuel through the cell over the anode electrode and a cathode flow field for carrying an oxygen containing gas through the cell over the cathode electrode, the fuel cell system also including a source of organic fuel, a fuel processing system to convert the organic fuel to hydrogen, and a burner, the fuel processing system comprising a plurality of fuel processing components including a reformer upstream of and in series with a shift converter, the steps of:a. disconnecting the primary load from the cell and halting the processing of organic fuel within the fuel processing system to produce hydrogen; b. after step (a), directing air and organic fuel from the source into the burner in a ratio selected to result in burner combustion products consisting of inert gases; and c. passing at least a portion of the burner combustion products of step (b) through at least the reformer of the fuel processing system at least until the reformer has been purged of residual hydrogen and carbon monoxide.