FUEL CELL

摘要

PROBLEM TO BE SOLVED: To provide a fuel cell capable of making small concentration overvoltage in a downstream oxidizing gas passage and suppressing drying of the electrolyte in an upstream oxidizing gas passage even in non-humidifying or low-humidifying operation. SOLUTION: (1) The fuel cell 10 is constituted so that the flowing directions of a fuel gas passage 27 and an oxidizing gas passage 28 installed through an electrolyte membrane 11 counter each other, and the cross section area of the fuel gas passage 27 is widened from the upstream part to the downstream part in the fuel gas flow direction and the cross section area of the oxidizing gas passage 28 is narrowed from the upstream part to the downstream part in the oxidizing gas flow direction. (2) A coolant is made to flow in the same direction as air. (3) The passage is segmented and made to meander. (5) The gas passage is formed in a trapezoidal shape and combined so that an external shape becomes rectangle. And (6) the gas passage cross section area is constant in width and variable in depth.