Abstract: A membrane electrode subassembly includes an ion conducting membrane and a microporous layer having microtextured surfaces. Complementary features of the microtextured surfaces may be formed as grooves, ridges, pyramids or other shapes. Features of the microtextured surface of the ion conducting membrane engage features of the microporous layer. The engagement of the features of the microtextured surfaces may involve an interlocking fit, a tongue and groove fit, or another type of engagement. A thin catalyst layer is disposed between the microtextured surfaces. The microtextured surfaces increase the surface area at the catalyst layer interfaces.

Abstract: A flexible flow field separator includes a substrate layer formed of a flexible material and having first and second surfaces. A structured flow field pattern is defined on the first surface of the substrate layer. The structured flow field pattern defines one or more fluid channels. The separator includes a first layer formed of one or more metals and disposed on the first surface of the substrate layer. The first layer is formed of an electrically conductive material. The separator further includes a second layer disposed on the second surface of the substrate layer. The second layer is formed of a flexible electrically conductive material. The first layer contacts the second layer at one or more locations to define an electrical connection between the first and second layers.

Abstract: Components that include catalyst layers used in membrane electrode assemblies (MEAs), and methods of making such components are described. The catalyst layers yield more uniform current distributions across the active area of the MEA during operation. The catalyst layers may have a uniform catalyst activity profile of a less active catalyst to achieve more uniform current density over the MEA active area. The catalyst layers may have a variable activity profile, such as an activity profile with a varying slope, to compensate for the inherent nonlinearities of catalyst utilization during operation of an electrochemical fuel cell. Desired variable catalyst activity profiles may be achieved, for example, by varying the catalyst loading across the MEA from inlet to outlet ports or by varying the surface area of the catalyst loading or by varying the surface area of the catalyst support elements.

Abstract: Nanostructured thin film catalysts which may be useful as fuel cell catalysts are provided, the catalyst materials including intermixed inorganic materials. In some embodiments the nanostructured thin film catalysts may include catalyst materials according to the formula PtxM(1-x) where x is between 0.3 and 0.9 and M is Nb, Bi, Re, Hf, Cu or Zr. The nanostructured thin film catalysts may include catalyst materials according to the formula PtaCobMc where a+b+c=1, a is between 0.3 and 0.9, b is greater than 0.05, c is greater than 0.05, and M is Au, Zr, or Ir. The nanostructured thin film catalysts may include catalyst materials according to the formula PtaTibQc where a+b+c=1, a is between 0.3 and 0.9, b is greater than 0.05, c is greater than 0.05, and Q is C or B.

Abstract: A fuel cell catalyst is provided comprising nanostructured elements comprising microstructured support whiskers bearing a thin film of nanoscopic catalyst particles, where the thin film of nanoscopic catalyst particles is made by alternating application of first layers comprising catalyst material, such as platinum or a platinum alloy, and second layers comprising a vacuum sublimable organic molecular solid, such as an aromatic organic pigments such as perylene red or a pthalocyanine

Abstract: Components that include catalyst layers used in membrane electrode assemblies (MEAs), and methods of making such components are described. The catalyst layers yield more uniform current distributions across the active area of the MEA during operation. The catalyst layers may have a uniform catalyst activity profile of a less active catalyst to achieve more uniform current density over the MEA active area. The catalyst layers may have a variable activity profile, such as an activity profile with a varying slope, to compensate for the inherent nonlinearities of catalyst utilization during operation of an electrochemical fuel cell. Desired variable catalyst activity profiles may be achieved, for example, by varying the catalyst loading across the MEA from inlet to outlet ports or by varying the surface area of the catalyst loading or by varying the surface area of the catalyst support elements.

Abstract: A fuel cell assembly includes first and second compression members. Two or more membrane electrode assembly (MEA) stacks are disposed between the compression members, each MEA stack having a positive and negative end. A first current collector is electrically coupled to a positive end of a first stack of the MEA stacks. A second current collector is electrically coupled to a negative end of a second stack of the MEA stacks. A current shunt is disposed between the compression members and electrically couples the MEA stacks.

Abstract: A gas diffusion layer incorporating a gasket (GIG) is described along with assemblies incorporating the GIG subassembly. Processes for making the GIG and membrane electrode assemblies (MEAs) incorporating the GIG are also described. A GIG subassembly includes a gas diffusion layer (GDL) and a gasket bonded to the GDL. The gasket includes a first gasket layer and a second gasket layer. The second gasket layer is formed of a gasket material in contact with the first gasket layer and the GDL. The gasket material of the second gasket layer bonds the GDL to the first gasket layer. An adhesive layer, and optionally a removable adhesive liner, is disposed on a surface of the first gasket layer opposite the second gasket layer. In some MEA configurations, the GDL is disposed within an aperture in the first gasket layer.

Abstract: A simple and inexpensive method of making a flow field plate that exhibits increased durability under conditions of use is provided. In some embodiments, the method includes the steps of applying a dry carbon powder to a flow field surface of the flow field plate and buffing the carbon powder onto the flow field surface. In some embodiments, the method includes the steps of rubbing a flow field surface of the flow field plate with a dry carbon solid and optionally buffing the carbon onto the flow field surface.

Abstract: In some embodiments, the present disclosure provides a fuel cell catalyst having a catalyst surface bearing a non-occluding layer of iridium. In some embodiments, the present disclosure provides a fuel cell catalyst comprising a catalyst surface bearing a sub-monolayer of iridium. In some embodiments, the present disclosure provides a fuel cell catalyst comprising a catalyst surface bearing a layer of iridium having a planar equivalent thickness of between 1 and 100 Angstroms. In some embodiments, the fuel cell catalyst comprises nanostructured elements comprising microstructured support whiskers bearing a thin film of nanoscopic catalyst particles. The layer of iridium typically has a planar equivalent thickness of between 1 and 100 Angstroms and more typically between 5 and 60 Angstroms. The fuel cell catalyst typically comprises no electrically conductive carbon material and typically comprises at least a portion of the iridium in the zero oxidation state.

Abstract: A fuel cell cathode catalyst is provided comprising nanostructured elements comprising microstructured support whiskers bearing nanoscopic catalyst particles; wherein the catalyst comprises platinum and manganese and at least one other metal selected from the group consisting of Group VIb metals, Group VIIb metals and Group VIIIb metals other than platinum and manganese; wherein the volume ratio of platinum to the sum of all other metals in the catalyst is between about 1 and about 4 and wherein the Mn content is equal to or greater than about 5 micrograms/cm2 areal density. Typically, the volume ratio of manganese to the at least one other metal is between 10:90 and 90:10. Typically, the at least one other metal is Ni or Co. In addition, a fuel cell MBA comprising the present cathode catalyst is provided. In addition, methods of making the present cathode catalyst are provided.

Abstract: A fuel cell cathode catalyst is provided which comprises nanostructured elements comprising microstructured support whiskers bearing nanoscopic catalyst particles. The nanoscopic catalyst particles are made by the alternating application of first and second layers, the first layer comprising platinum and the second layer being an alloy or intimate mixture of iron and a second metal selected from the group consisting of Group VIb metals, Group VIIb metals and Group VIIIb metals other than platinum and iron, where the atomic ratio of iron to the second metal in the second layer is between 0 and 10, where the planar equivalent thickness ratio of the first layer to the second layer is between 0.3 and 5, and wherein the average bilayer planar equivalent thickness of the first and second layers is less than 100 ?.

Abstract: The present disclosure provides a simple and inexpensive method of making a flow field plate that exhibits increased durability under conditions of use comprising the steps of: a) providing a flow field plate comprising at least one flow field surface; b) applying a dry carbon powder to at least one flow field surface of the flow field plate; and c) buffing the carbon powder onto the flow field surface. In another aspect, the present disclosure provides a method of making a coated flow field plate comprising the steps of: a) providing a flow field plate comprising at least one flow field surface; b) rubbing at least one flow field surface of the flow field plate with a dry carbon solid; and optionally c) buffing the carbon onto the flow field surface.

Abstract: A gas diffusion layer incorporating a gasket (GIG) is described along with assemblies incorporating the GIG subassembly. Processes for making the GIG and membrane electrode assemblies (MEAs) incorporating the GIG are also described. A GIG subassembly includes a gas diffusion layer (GDL) and a gasket bonded to the GDL. The gasket includes a first gasket layer and a second gasket layer. The second gasket layer is formed of a gasket material in contact with the first gasket layer and the GDL. The gasket material of the second gasket layer bonds the GDL to the first gasket layer. An adhesive layer, and optionally a removable adhesive liner, is disposed on a surface of the first gasket layer opposite the second gasket layer. In some MEA configurations, the GDL is disposed within an aperture in the first gasket layer.

Abstract: Fabrication methods for making a gas diffusion layer incorporating a gasket (GIG) fuel cell subassemblies via roll-to-roll processes are described. A material processable by one or both of heat and pressure having spaced apart apertures is transported to a bonding station. A first gasket layer having gas diffusion layers arranged in relation to spaced apart apertures of a first gasket layer is transported to the bonding station. The heat/pressure processable material is aligned with the first gasket layer and the gas diffusion layers. At the bonding station, the heat/pressure processable material is bonded to the first gasket layer and the gas diffusion layers. After bonding, the heat/pressure processable material forms a second gasket layer that attaches the gas diffusion layers to the first gasket layer.

Abstract: A proton exchange membrane fuel cell stack includes two or more plate assemblies stacked together. Each plate assembly includes a membrane electrode assembly (MEA) disposed between a first plate and second plate. One of the first and second plates is an anode plate and the other is a cathode plate. The first and second plates each include a first side facing the MEA and a second side facing away from the MEA. The plates include flow fields on the first sides and gas manifold holes coupled to gas distribution passages of the fuel cell stack. The first plates each further include a flow path carrying gases from at least one of the gas manifold holes to the flow field of the first plate. The flow path is formed at least in part by channels on the second side of an adjacent second plate when the plate assemblies are stacked together.

Abstract: A fuel cell assembly includes first and second compression members at first and second ends of the fuel cell assembly. A membrane electrode assembly (MEA) stack is disposed between the compression members. The MEA stack includes a fluid flow passage that allows gases to flow between the first and second ends of the fuel cell assembly. A fastening member connecting the first and second compression members and is disposed within the fluid flow passage of the MEA stack.

Abstract: A fuel cell assembly includes two or more plate assemblies stacked together. Each plate assembly includes a membrane electrode assembly (MEA) sandwiched between an anode plate and a cathode plate. At least one of the anode plate and the cathode plate has a first flow field on a side facing the MEA and a second flow field on a side facing away from the MEA. The first flow field is of a first uniform depth, and the second flow field is of a second uniform depth. In one configuration, the first and second uniform depths are the same.

Abstract: A fuel cell assembly includes first and second compression members. Two or more membrane electrode assembly (MEA) stacks are disposed between the compression members, each MEA stack having a positive and negative end. A first current collector is electrically coupled to a positive end of a first stack of the MEA stacks. A second current collector is electrically coupled to a negative end of a second stack of the MEA stacks. A current shunt is disposed between the compression members and electrically couples the MEA stacks.

Abstract: A fuel cell assembly includes a membrane electrode assembly (MEA) stack has a plurality of stacked planar membranes. The MEA stack further includes gas passageways arranged so that anode and cathode gases flow perpendicular to the planar membranes between a first side and a second side of the fuel cell assembly. Anode gas inlet and outlet ports and cathode gas inlet and outlet ports are disposed on the first side of the fuel cell assembly and coupled to the gas passageways of the MEA stack.