Gas diffusion electrode for membrane fuel cells and method of making same

摘要

A gas diffusion electrode for membrane fuel cells consists of a finely divided electro-catalyst which is dispersed in a proton conducting polymer membrane. The overall porosity of the electrode is > 40 and < 75%. Also claimed is a process for producing such an electrode by coating the membrane with a dispersion of a finely divided electro-catalyst and a pore forming material in a solution of an ionic conducting polymer. The polymer membrane is in a non-azide temperature stable modification and during the coating is heated to 130 to 170 degrees C. The coating is dried, the membrane and coating are protonated in an acid. The pore forming material has a particle size of 0.1 to 10 mu m.