Abstract: The present invention relates to a gas diffusion layer for a fuel cell, made of a carbon substrate grafted with at least one aromatic group having formula (II): wherein: the asterisk * designates a carbon atom with no hydrogen and no Ri group, with i=1 to 5, and covalently bonded to the carbon substrate; at least two of the R1, R2, R3, R4, and R5 groups are different from a hydrogen atom; at least two of the R1, R2, R3, R4, and R5 groups are hydrophobic groups or hydrophilic groups or a hydrophobic group and a hydrophilic group.

Abstract: A method of attachment between a metal collector and a carbon felt of a battery includes the steps of impregnation of the pores of the carbon felt with a mixture of metal powder and of a binder, locally performed in at least one predetermined area of the carbon felt; and spot welding between the metal collector and the carbon felt impregnated with the metal powder, performed at the level of said at least one predetermined area.

Abstract: A method of treating a carbon substrate, includes the successive steps of impregnating the carbon substrate with an aqueous solution containing an amorphous fluorinated copolymer of tetrafluoroethylene and of perfluoromethoxy dioxole, drying the carbon substrate at a pressure lower than the atmospheric pressure, and obtaining a carbon substrate impregnated with a fluorinated copolymer. Such a carbon substrate may be used as a gas diffusion layer in a fuel cell.

Abstract: The invention relates to a fabric comprising carbon threads, said fabric having a mass per unit area within the range of 40 g/m2 to 100 g/m2, preferably from 40 g/m2 to 80 g/m2, specifically from 60 g/m2 to 80 g/m2, and characterized in that it comprises staple fibers, said staple fibers extending out from the threads constituting the fabric from which they originate and extending in a direction that is not parallel to the direction of the thread from which they originate and/or in that the fabric is needled. The invention also relates to the use of this fabric in a diffusion layer for a fuel cell and a method for manufacturing this diffusion layer.

Abstract: A method of attachment between a metal collector and a carbon felt of a battery includes the steps of impregnation of the pores of the carbon felt with a mixture of metal powder and of a binder, locally performed in at least one predetermined area of the carbon felt; and spot welding between the metal collector and the carbon felt impregnated with the metal powder, performed at the level of said at least one predetermined area.

Abstract: The present invention relates to a gas diffusion layer for a fuel cell, made of a carbon substrate grafted with at least one aromatic group having formula (II): wherein: the asterisk * designates a carbon atom with no hydrogen and no Ri group, with i=1 to 5, and covalently bonded to the carbon substrate; at least two of the R1, R2, R3, R4, and R5 groups are different from a hydrogen atom; at least two of the R1, R2, R3, R4, and R5 groups are hydrophobic groups or hydrophilic groups or a hydrophobic group and a hydrophilic group.

Abstract: A method of treating a carbon substrate, includes the successive steps of impregnating the carbon substrate with an aqueous solution containing an amorphous fluorinated copolymer of tetrafluoroethylene and of perfluoromethoxy dioxole, drying the carbon substrate at a pressure lower than the atmospheric pressure, and obtaining a carbon substrate impregnated with a fluorinated copolymer. Such a carbon substrate may be used as a gas diffusion layer in a fuel cell.