Abstract: An aqueous coating composition is provided comprising carbon particles, one or more highly fluorinated polymers and one or more amine oxide surfactants, typically an amine oxide surfactant according to formula I: 1

Abstract: An aqueous coating composition is provided comprising carbon particles, one or more highly fluorinated polymers and one or more amine oxide surfactants, typically an amine oxide surfactant according to formula I: where n is 9 to 19. The coating composition is advantageously used in a method of making a gas diffusion layer for an electrochemical cell comprising the steps of: a) coating a electrically conductive porous substrate with the aqueous coating composition, and b) heating the electrically conductive porous substrate to a temperature sufficient to decompose the amine oxide surfactants. In another aspect, a gas diffusion layer for an electrochemical cell is provided which is advantageously free of surfactant.

Abstract: A method is provided for making a gas diffusion layer (GDL) for an electrochemical cell comprising the steps of coating a surface of a plain-weave carbon fiber cloth with a layer comprising carbon particles and one or more highly fluorinated polymers to make a coated plain-weave carbon fiber cloth, and compressing the coated plain-weave carbon fiber cloth to a compression of 25% or greater. Typically the GDL according to the present invention can be incorporated into a membrane electrode assembly (MEA) comprising a very thin polymer electrolyte membrane (PEM), typically having a thickness of 50 microns or less, without increased shorting across the PEM even when the MEA is under compression.

Abstract: An aqueous coating composition is provided comprising carbon particles, one or more highly fluorinated polymers and one or more amine oxide surfactants, typically an amine oxide surfactant according to formula I: 1

Abstract: A method is provided for making a gas diffusion layer for an electrochemical cell comprising the steps of: a) combining carbon particles and one or more surfactants in a typically aqueous vehicle to make a preliminary composition, typically by high shear mixing; b) adding one or more highly fluorinated polymers to said preliminary composition by low shear mixing to make a coating composition; and c) applying the coating composition to an electrically conductive porous substrate, typically by a low shear coating method.