Patent ID: 7803475

Claim:
A fuel cell stack, comprising a plurality of adjacently stacked fuel cell modules each of which includes a plurality of adjacently aligned fuel cells that are connected in electrical series and a proton exchange membrane, said plurality of adjacently aligned fuel cells including a first fuel cell and a second fuel cell, said first fuel cell including a first anode diffusion media and a first cathode diffusion media and said second fuel cell including a second anode diffusion media and a second cathode diffusion media, said first anode diffusion media and said second cathode diffusion media being located adjacent one another on a first side of said proton exchange membrane and said second anode diffusion media and said first cathode diffusion media being located adjacent one another on a second side of said proton exchange membrane opposite said first side, wherein a first seal is disposed between said first cathode diffusion media and said second anode diffusion media and a second seal is disposed between said first anode diffusion media and said second cathode diffusion media, said first seal being fluid impermeable and electrically conductive to provide current flow between adjacent fuel cells from said first cathode diffusion media to said second anode diffusion media, said second seal being fluid impermeable and electrically non-conductive and inhibiting current flow between said first anode diffusion media and said second cathode diffusion media.