Fuel-cell unit cell

A fuel-cell unit cell for making up a fuel cell stack in which a plurality of fuel-cell unit cells are stacked while a cathode-side separator and an anode-side separator of neighboring fuel-cell unit cells are in contact with each other, the fuel-cell unit cell comprising:

• a membrane electrode and gas diffusion layer assembly;
• a cathode-side separator made of a press-molded plate, the cathode-side separator forming a plurality of cathode gas flow paths and non-flow-path portions therebetween on a cathode-side surface of the membrane electrode and gas diffusion layer assembly;
• and
• an anode-side separator made of a press-molded plate, the anode-side separator forming a plurality of anode gas flow paths and non-flow-path portions therebetween on an anode-side surface of the membrane electrode and gas diffusion layer assembly, wherein
• at least one gas flow path among the plural cathode gas flow paths and the plural anode gas flow paths includes a constricting portion that is configured to reduce a flow-path height in a stacking direction of the fuel-cell unit cells as well as to reduce a flow path cross-sectional area of the gas flow path, and
• when projected and observed along the stacking direction, the plural cathode gas flow paths and the plural anode gas flow paths are configured to have mutually different two-dimensional shapes, there exist intersect positions at which the cathode gas flow paths and the anode gas flow path intersect each other, and the constricting portion is provided at a position other than the intersect positions.