Fuel cell stack and method of producing dummy cell

A method of producing a dummy cell provided at least at one end of a stack body of a fuel cell stack in a stacking direction,

• the fuel cell stack comprising:
• the stack body including a plurality of power generation cells stacked in the stacking direction, the power generation cells each comprising a membrane electrode assembly including an electrolyte membrane and electrodes provided on both sides of the electrolyte membrane, the electrodes each having a gas diffusion layer of electrically conductive porous body, and a resin frame member provided around an outer periphery of the membrane electrode assembly,
• the method comprising:
• a dummy structural body forming step of obtaining a dummy structural body corresponding to the membrane electrode assembly by stacking a first electrically conductive porous body, a second electrically conductive porous body having a surface size smaller than that of the first electrically conductive porous body, and a third electrically conductive porous body having a surface size smaller than that of the second electrically conductive porous body together in this order;
• and
• a joining step of joining the dummy structural body and the dummy resin frame member provided around an outer periphery of the dummy structural body together,
• wherein the first electrically conductive porous body includes a first outer peripheral portion extending outside an outer peripheral end surface of the second electrically conductive porous body;
• the second electrically conductive porous body includes a second outer peripheral portion extending outside an outer peripheral end surface of the third electrically conductive porous body;
• and
• in the joining step, an adhesive interposed between the first and second outer peripheral portions and an inner periphery of the dummy resin frame member is hardened to form an adhesive layer which adheres the first and second outer peripheral portions and the dummy resin frame member to each other.