GAS DIFFUSION ELECTRODE AND SOLID POLYMER ELECTROLYTE FUEL CELL

摘要

A gas diffusion electrode includes: an electrode catalyst layer 13; microporous layers 11 and 12 arranged on the electrode catalyst layer 13 and including at least two layers which are second and first microporous layers 12 and 11 formed of materials having different water repellencies, wherein the second microporous layer 12 disposed on the electrode catalyst layer 13 side is composed to have higher water repellency than the first microporous layer 11; and an oxidant gas diffusion substrate 10 disposed on the microporous layers 11 and 12 and formed of carbon fiber. According to the gas diffusion electrode of the present invention, drainability of generated water from the electrode catalyst layer to the gas diffusion layer and moisture retention and gas diffusibility of the electrode catalyst layer can be enhanced. Moreover, according to a solid polymer electrolyte fuel cell of the present invention, stable power generation characteristics can be obtained even under an operating condition with wide humidity range and current density range.