Composite electrolyte membrane, catalyst-coated membrane assembly, membrane-electrode assembly and polymer electrolyte fuel cell

摘要

To provide a polymer electrolyte membrane having excellent size stability and excellent mechanical strength that can sufficiently prevent the size change due to the swelling condition, the displacement of the polymer electrolyte membrane and the formation of wrinkles during the production of the polymer electrolyte fuel cell, and can prevent damage during the production and operation of the polymer electrolyte fuel cell. In a composite electrolyte membrane including a porous reinforcement layer made of a resin and an electrolyte layer made of a polymer electrolyte and laminated at least one main surface of the reinforcement layer, the direction having a high tensile modulus of elasticity in the reinforcement layer is substantially corresponded with the direction having a high rate of size change in the electrolyte layer.