Patent ID: 7060384

Claim:
A polymer electrolyte fuel cell comprising: an ion conductive polymer electrolyte membrane; a pair of gas diffusion electrodes sandwiching said polymer electrolyte membrane therebetween, thereby forming a polymer electrolyte membrane-electrode assembly; and a pair of separator plates sandwiching therebetween said polymer electrolyte membrane-electrode assembly, and having gas flow channels facing respective ones of said pair of gas diffusion electrodes, each of said gas flow channels having an inlet and an outlet, wherein each of said pair of gas diffusion electrodes has a catalyst layer in contact with said polymer electrolyte membrane and a gas diffusion layer in contact with a respective catalyst layer, wherein each of said gas diffusion layers comprises a porous carbon supporting body, wherein each of said porous carbon supporting bodies comprises at least a first porous carbon layer and a second porous carbon layer, said first porous carbon layer facing a corresponding one of said catalyst layers, and wherein said first porous carbon layer has a larger number of smaller pores distributed therein as compared with said second porous carbon layer, said second porous carbon layer having a smaller number of larger pores distributed therein as compared with said first porous carbon layer, wherein each of said pair of gas diffusion layers comprises an electrically conductive polymer-containing layer provided thereon at a catalyst layer side thereof, wherein said electrically conductive polymer-containing layer comprises a polymer material and electrically conductive carbon particles, wherein in at least one of said electrically conductive polymer-containing layers comprising said polymer material and said electrically conductive carbon particles, said electrically conductive carbon particles comprise first carbon particles and second carbon particles having a larger amount of acidic functional groups than that of said first carbon particles, and wherein the weight ratio of said second carbon particles, relative to said first carbon particles, increases from one end of said gas diffusion layer, corresponding to said inlet of said gas flow channel, to the other end of said gas diffusion layer corresponding to said outlet of the gas flow channel.