GAS DIFFUSION LAYER OF SOLID POLYMER FUEL CELL, MEMBRANE-ELECTRODE ASSEMBLY OF SOLID POLYMER FUEL CELL INCLUDING GAS DIFFUSION LAYER, AND SLURRY USED FOR MANUFACTURING GAS DIFFUSION LAYER

摘要

PROBLEM TO BE SOLVED: To provide a gas diffusion layer which simultaneously achieves high gas permeability and high conductivity, even when compressive pressure is applied to the gas diffusion layer in order to obtain a stack structure.SOLUTION: A membrane-electrode assembly comprises a porous aggregate structure 30 composed of thermally fusible organic fibers OF which can be thermally fused to each other by heating. In the porous aggregate structure 30, carbon fibers CF are bound each other by a binder resin along with conductive particulates, so that the porous aggregate structure 30 having relatively high rigidity is formed in gas diffusion layers 18 and 20 by mutual binding of relatively low amounts of thermally fusible organic fibers OF. Furthermore, since the thermally fusible organic fibers OF has a fiber length within the range of 0.2 to 3 of a ratio of the film thickness of the gas diffusion layer to the fiber length, (the film thickness of the gas diffusion layer)/(the fiber length) it is possible to obtain the gas diffusion layers 18 and 20 which simultaneously achieve high gas permeability and high conductivity, even when compressive pressure is applied.