A fuel cell stack that includes straight cathode flow channels and straight anode flow channels through a seal area between bipolar plates in the stack. The fuel cell stack includes a seal that extends around the active area of the stack and between the stack headers and the active area. At the locations where the cathode flow channels extend through a seal area to the cathode input header and the cathode outlet header, and the anode flow channels extend through a seal area to the anode input header and the anode output header, the diffusion media layer on one side of the membrane is extended to provide the seal load. Alternately, shims can be used to carry the seal load.