Electrode catalyst layer, membrane electrode assembly, and polymer electrolyte fuel cell

Abstract

To provide an electrode catalyst layer, a membrane electrode assembly, and a polymer electrolyte fuel cell capable of improving the mass transport properties and proton conduction properties in the electrode catalyst layer and exhibiting high power generation performance for a longer time. An electrode catalyst layer according to an embodiment of the present invention is an electrode catalyst layer configured to be bonded to a polymer electrolyte membrane for use in a polymer electrolyte fuel cell, the electrode catalyst layer including: a catalytic substance; a conductive carrier supporting the catalytic substance; a polymer electrolyte; and one or more types of fibers containing at least a polymer fiber, wherein, among the fibers, the number of fibers having an axis inclination θ of 0°<θ<45° relative to a bonding surface between the polymer electrolyte membrane and the electrode catalyst layer is more than 50% of the total number of the contained fibers.

Dependencies are inferred from the claim text.