Fuel cell module, fuel cell stack, and manufacturing method of fuel cell module

A fuel cell module comprising:

• a membrane-electrode assembly including
• a polymer electrolyte membrane,
• an anode catalyst layer disposed on a first main surface of the polymer electrolyte membrane,
• a cathode catalyst layer disposed on a second main surface of the polymer electrolyte membrane, and
• a pair of gas diffusion layers, one of which is laminated on the anode catalyst layer and the other of which is laminated on the cathode catalyst layer;
• a pair of separators sandwiching the membrane-electrode assembly therebetween;
• and
• a sealing member bonding and sealing the membrane-electrode assembly and each of the pair of separators together,
• wherein an overlapping region is provided in which one gas diffusion layer of the pair of gas diffusion layers and the sealing member overlap each other in a thickness direction, the overlapping region including a center-side edge of the sealing member,
• the one gas diffusion layer has a first surface and a second surface, the first and second surfaces being disposed on opposite sides of the one gas diffusion layer with respect to the thickness direction, and the one gas diffusion layer is notched so as to penetrate between the first surface and the second surface in the thickness direction at a portion of the one gas diffusion layer within the overlapping region, and
• wherein the portion of the one gas diffusion layer within the overlapping region includes a serrated portion formed in a saw teeth shape in plan view.