| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent drying of an electrolyte membrane in a gas inlet of a gas passage upstream and prevent water clogging on the interface between a catalyst layer and a diffusion layer and within the diffusion layer in a gas outlet of the gas passage downstream in a membrane-electrode assembly of a fuel cell. <P>SOLUTION: In the fuel cell in which a fuel gas passage 51 is formed on one side of the membrane-electrode assembly 1 formed by arranging catalyst layers 31, 32 constituting electrodes 21, 22 and diffusion layers 41, 42 on both surfaces of the electrolyte membrane 11, and an oxidant gas passage 61 is formed on the other side, the diffusion layers 41, 42 are formed with a water repellent microporous layer 41, and pore sizes are formed so that the sizes of pores 4a are made small from the catalyst layer 31, 32 toward the gas passages 51, 61 in the upstream regions of the gas passages 51, 61, where are required to prevent drying, and the sizes of pores 4b are made large from the catalyst layers 31, 32 toward the gas passages 61, 62 in the downstream regions of the gas passages 51, 61, where are required to prevent flooding. <P>COPYRIGHT: (C)2008,JPO&INPIT |
