Abstract: A novel anode structure for making a proton exchange membrane fuel cell (PEMFC) tolerant to incidences of cell reversal includes an electrocatalyst layer having at least one electrocatalyst and at least one proton conducting polymer. The anode structure also includes one or more water retaining material(s), such as carbon nanofibers, embedded within the electrocatalyst layer.

Abstract: The present invention relates to a membrane electrode assembly wherein each gas diffusion substrate comprises a porous electrically conductive gasket member is located on the first and second planar faces of a peripheral portion of the sheet material. The electrocatalyst layers are not present adjacent to the gasket members and the edge of the membrane is sandwiched between the gasket members. The invention further relates to integrated cell assemblies and fuel cell stacks comprising membrane electrode assemblies according to the invention.

Abstract: A novel proton conducting polymer membrane comprising a series of channels and/or capillaries (2) for use in MEAs and fuel cells is provided. Such a membrane allows a supply of water from an external source to be supplied to said membrane allowing water electrolysis to be maintained during incidences of cell reversal in an MEA or fuel cell comprising said membrane. Methods for the construction of such a membrane are also provided.

Abstract: A novel flexible non-woven carbon fibre gas diffusion substrate comprising a plurality of first carbon fibres orientated in the x-, y- and optionally z-directions, said first fibres being bonded with a thermoplastic polymeric substance, and a carbon based filler material, characterised, in that the flexible non-woven carbon fibre gas diffusion substrate has a total density of greater than 0.35 g/cm3, and a gas diffusion electrode obtained therefrom is disclosed. Also disclosed is a process for the manufacture of the substrate and electrode.

Abstract: A fuel cell gas diffusion substrate has primary fibres, secondary fibres and one or more thermoplastic polymers for binding the primary and secondary fibres, characterized in that the secondary fibers are in the form of carbon nanofibers, and a gas diffusion electrode and membrane electrode assembly prepared therefrom are disclosed.

Abstract: A substrate, suitable for the preparation of a composite membrane, which substrate comprises a porous matrix of fibres, characterised in that the fibres comprise mixed amorphous silica fibres that are bound with a binder, a composite membrane comprising the substrate and a process for the preparation of the substrate and composite membrane is disclosed.

Abstract: The present invention relates to a membrane electrode assembly wherein each gas diffusion substrate comprises a porous electrically conductive gasket member is located on the first and second planar faces of a peripheral portion of the sheet material. The electrocatalyst layers are not present adjacent to the gasket members and the edge of the membrane is sandwiched between the gasket members. The invention further relates to integrated cell assemblies and fuel cell stacks comprising membrane electrode assemblies according to the invention.

Abstract: A process for the preparation of a membrane includes forming a porous substrate and then impregnating the porous substrate with a polymeric material. The porous substrate is made by first dispersing fibres in water to form a slurry, then depositing the slurry onto a mesh bed to form a fibre network, drying and compacting the fibre network, and, either before or after drying and compacting, applying to the fibre network a dispersion of a binder of silica and a fluorinated polymer.

Abstract: A process for preparing a solid polymer electrolyte membrane comprising an ion-conducting polymer, a catalyst and a high surface area support material, which process comprises: (a) associating the catalyst with the support material to form a catalysed support; and (b) combining the catalysed support with an ion-conducting polymer composition; is disclosed.

Abstract: A novel anode structure for making a proton exchange membrane fuel cell (PEMFC) tolerant to incidences of cell reversal, said anode structure comprising an electrocatalyst layer wherein said electrocatalyst layer comprises at least one electrocatalyst and at least one proton conducting polymer, characterised in that one or more water retaining material(s) are embedded within the electrocatalyst layer, and a process for the preparation thereof is disclosed. Also disclosed is a novel electrocatalyst ink for use in the preparation of the novel anode structure.

Abstract: A novel flexible non-woven carbon fibre gas diffusion substrate comprising a plurality of first carbon fibres orientated in the x-, y- and optionally z-directions, said first fibres being bonded with a thermoplastic polymeric substance, and a carbon based filler material, characterised, in that the flexible non-woven carbon fibre gas diffusion substrate has a total density of greater than 0.35 g/cm3, and a gas diffusion electrode obtained therefrom is disclosed. Also disclosed is a process for the manufacture of the substrate and electrode.

Abstract: An electrocatalyst ink comprising one or more electrocatalyst metals and one or more proton-conducting polymers, characerised in that the electrocatalyst ink further comprises an electron-conducting fibrous material, and a process for the preparation of said ink is disclosed. The use of the ink in a gas diffusion electrode, particularly for use in PEM fuel cells is also disclosed.

Abstract: A novel non-woven fiber web comprising a plurality of first fibers orientated in the x-, y-, and optionally z-directions, said first fibers being bonded with a polymeric substance, characterised in that one or more continuous strands are embedded within the sub-surface layer of the non-woven fiber web, each continuous strand comprising a plurality of second carbon fibers, is disclosed. A gas diffusion substrate, electrode and membrane electrode assembly comprising said web is also disclosed, all of which may have application in electrochemical devices, for example in a fuel cell.

Abstract: A fuel cell gas diffusion substrate comprising primary fibres, secondary fibres and one or more thermoplastic polymers for binding said primary and secondary fibres, characterised in that said secondary carbon fibres are in the form of carbon nanofibres, and a gas diffusion electrode and membrane electrode assembly prepared therefrom are disclosed.

Abstract: A novel gas diffusion substrate comprising a porous structure and a filler material, characterised in that the filler material comprises a base filler material which is electrically conducting and carbonaceous and one or more modifier materials which ate hydrophilic in nature relative to the base filler material; a porous gas diffusion electrode comprising said substrate and the use of said substrate or electrode in a fuel cell is disclosed.

Abstract: A novel proton conducting polymer membrane comprising a series of channels and/or capillaries (2) for use in MEAs and fuel cells is provided. Such a membrane allows a supply of water from an external source to be supplied to said membrane allowing water electrolysis to be maintained during incidences of cell reversal in an MEA or fuel cell comprising said membrane. Methods for the construction of such a membrane are also provided.

Abstract: A non-woven fibre web comprising a plurality of first fibres of amorphous silica, said first fibres being orientated in the x-, y- and optionally z-direction, and optionally being bonded with one or more binder substances, characterised in that one or more continuous strands are embedded within the non-woven fibre web, each continuous strand comprising one or more second fibres of amorphous silica, and a method for the manufacture thereof is disclosed. Also disclosed is an ion-conducting membrane comprising said non-woven web and the use thereof, in particular, in a fuel cell.

Abstract: A novel composite membrane comprising a porous substrate of randomly orientated individual fibres and at least one ion conducting polymer, characterised in that the ion conducting polymer is embedded within the porous substrate, a process for its preparation and its use, particularly in fuel cells is disclosed.