Gas diffusion electrode comprising a structure which influences its physical characteristics

摘要

The invention relates to a gas diffusion electrode comprising a concentration gradient of a chemical substance in at least one direction that is parallel to the upper face of the gas diffusion electrode and a direction that is perpendicular to the upper face of said electrode. The invention also relates to a gas diffusion electrode comprising a layer thickness gradient. The gas diffusion electrodes are adapted to the inhomogeneous thermodynamic conditions in a fuel cell and at least partly compensate said conditions, in such a way that a membrane electrode assembly (MEA), which is equipped with gas diffusion electrodes of this type, produces an excellent, reliable performance. The invention further relates to methods for producing gas diffusion electrodes of this type, in addition to fuel cells and fuel cell stacks comprising electrodes of this type.