Power generation cell and fuel cell stack

A power generation cell comprising:

• a membrane electrode structure including a membrane electrode assembly and a frame member supporting a peripheral edge portion of the membrane electrode assembly, the membrane electrode assembly having an electrolyte membrane, a first gas diffusion electrode layer disposed along one surface of the electrolyte membrane, and a second gas diffusion electrode layer disposed along another surface of the electrolyte membrane;
• and
• a separator including a first separator and a second separator, the first separator being disposed facing one surface of the membrane electrode structure so as to form a first flow path through which a first reaction gas flows between the first separator and the membrane electrode structure, the second separator being disposed facing another surface of the membrane electrode structure so as to form a second flow path through which a second reaction gas flows between the second separator and the membrane electrode structure, wherein
• the first gas diffusion electrode layer includes a first gas diffusion layer to which the first reaction gas is supplied, and a first electrode catalyst layer disposed between the electrolyte membrane and the first gas diffusion layer,
• the second gas diffusion electrode layer includes a second gas diffusion layer to which the second reaction gas is supplied, and a second electrode catalyst layer disposed between the electrolyte membrane and the second gas diffusion layer,
• each of the first flow path and the second flow path includes a central flow path formed in a first region located at a central portion of the separator, an adjacent flow path formed in a second region adjacent to the first region, and an end flow path formed in a third region between a communication hole for a gas supply and discharge penetrating the separator and the second region,
• each of the first separator and the second separator has a plurality of protruding portions having a predetermined height of a substantially cylindrical shape protruding from each of the first separator and the second separator toward the membrane electrode structure in the second region,
• the predetermined height is set such that the plurality of protruding portions are spaced apart from the frame member by an amount corresponding to a thickness of each of the first gas diffusion layer and the second gas diffusion layer, and
• an end portion of the first gas diffusion layer and an end portion of the second gas diffusion layer are located within the second region.