a method for fabricating a fuel cell includes fixedly attaching a reinforcement to a proton - exchange membrane and to an electrode placed against a first face of the proton - exchange membrane . the reinforcement has a median aperture through which an interior portion of the electrode is exposed . fixedly attaching the reinforcement includes superimposing an inner edge of the reinforcement over a periphery of the electrode , and causing a projecting portion of the reinforcement to project the proton - exchange membrane so as to limit gas permeation into the proton - exchange membrane , and forming filigrees by a wet process in a gas diffusion layer , thereby forming a recess therein , and placing the gas diffusion layer so that the inner edge of the reinforcement extends into the recess in the gas diffusion layer .