Patent ID: 7858263

Claim:
A solid polymer electrolyte fuel cell which varies an output according to a demand load, comprising: a plurality of electrode structures comprising an anode and a cathode, each having a diffusion layer and a catalyst layer, and polymer electrolyte membrane held between the anode and the cathode; and a plurality of separators for holding the respective electrode structures, comprising a fuel gas passage for supplying and discharging fuel gas containing hydrogen on a surface opposing the anode; and an oxidant gas passage for supplying and discharging oxidant gas on a surface opposing the cathode, the electrode structures and the separators being stacked, wherein the catalyst layer of the anode comprises a mixture of an ion conductive material, a carbon, and either a platinum powder, platinum alloy powder, or both, all of the platinum powder, platinum alloy powder or both therein not supported on the carbon, and all of the carbon therein existing independently from the platinum powder, platinum alloy powder or both; and the catalyst layer of the cathode comprises a metal support mixture in which an ion conductive material used in the catalyst of the anode and an electro-conductive material which has a supported catalyst material, are mixed.