A fuel cell comprises an electrode plate having a flow field formed
therein and a proton exchange membrane. A compressible permeable
diffusion media is disposed adjacent the electrode plate. The diffusion
media is compressed against the electrode plate so that a portion of the
media intrudes into the flow field. A fuel cell stack can be made by
compressing a plurality these fuel cells together. The fuel cell stack is
compressed so that the diffusion media in each fuel cell is compressed
against the adjacent electrode plate with a portion of the media
intruding into the flow field in the adjacent electrode plate. The
compression of the fuel cell stack can be adjusted so that a magnitude of
intrusion of the diffusion media into the flow channels is adjusted and a
pressure drop of a predetermined magnitude occurs across the fuel cell
stack at a desired operational state.