Abstract: A disclosed method for coating a substrate with an ionomer, applies the ionomer as a component of a stable foam, then dries the applied foam layer. The substrate to be so coated, in particular embodiments, is an electrode substrate, with or without a catalyst layer applied thereon. In another embodiment, the substrate is an ion-exchange membrane. In yet more particular embodiments, the substrate is suitable for use in an electrochemical fuel cell. Also disclosed are products made by the disclosed methods, namely, ionomer-coated substrates, including ionomer-coated electrode substrates and electrodes. The foam layer may also comprise catalyst powder to form a catalyst layer. Membrane electrode assemblies, fuel cells, and fuel cell stacks that incorporate the substrates are also disclosed, as are motor vehicles, and stationary and portable electrical power-generating plants that incorporate the fuel cell stacks.

Abstract: A disclosed method for coating a substrate with an ionomer, applies the ionomer as a component of a stable foam, then dries the applied foam layer. The substrate to be so coated, in particular embodiments, is an electrode substrate, with or without a catalyst layer applied thereon. In another embodiment, the substrate is an ion-exchange membrane. In yet more particular embodiments, the substrate is suitable for use in an electrochemical fuel cell. Also disclosed are products made by the disclosed methods, namely, ionomer-coated substrates, including ionomer-coated electrode substrates and electrodes. The foam layer may also comprise catalyst powder to form a catalyst layer. Membrane electrode assemblies, fuel cells, and fuel cell stacks that incorporate the substrates are also disclosed, as are motor vehicles, and stationary and portable electrical power-generating plants that incorporate the fuel cell stacks.

Abstract: An ion-exchange membrane may be continuously coated by depositing a catalyst composition on a release surface, drying the catalyst at an elevated temperature and then transferring the dried catalyst layer onto an ion-exchange membrane by applying pressure at a different elevated temperature. Also disclosed is an apparatus for thus continuously coating an ion-exchange membrane. The catalyst coated membrane is of particular use in polymer electrolyte membrane (PEM) fuel cells for which a membrane electrode assembly may be prepared by bonding fluid distribution layers to the catalyst coated membrane.