Abstract: A fuel cell stack includes end plate units each having a metal plate, a dielectric plate, and a perimeter groove defined by the dielectric plate and an edge of the metal plate. The stack also includes a gas inlet and a coolant inlet configured to receive a reactant gas and coolant into the fuel cell stack, respectively, fuel cells having a pair of bipolar plates, and a multi-layer seal disposed within the fuel cell stack on the end plate units or the bipolar plates. The multi-layer seal includes a first layer constructed of a first material that is substantially impermeable to the reactant gas, and a second layer constructed of a second material that is more resistant to corrosion than is the first material.

Abstract: A method for performing one or more proactive remedial actions to prevent anode flow-field flooding in an anode side of a fuel cell stack at low stack current density. The method includes identifying one or more trigger conditions that could cause the anode flow-field to flood with water, and performing the one or more proactive remedial actions in response to the identified trigger conditions that removes water from the anode side flow-field prior to the anode flooding occurring.

Abstract: A membrane electrode assembly includes an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and a peroxide decomposition catalyst positioned in at least one position selected from the group consisting of a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system. The assembly components contain ionomer material which can be perfluorinated or non-perfluorinated, high temperature, hydrocarbon, and the like.

Abstract: A membrane electrode assembly includes an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and a peroxide decomposition catalyst positioned in at least one position selected from the group consisting of a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system. The assembly components contain ionomer material which can be perfluorinated or non-perfluorinated, high temperature, hydrocarbon, and the like.

Abstract: A membrane electrode assembly includes an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and a peroxide decomposition catalyst positioned in at least one position selected from the group consisting of a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system. The assembly components contain ionomer material which can be perfluorinated or non-perfluorinated, high temperature, hydrocarbon, and the like.

Abstract: A system and method for breaking-in and humidifying membrane-electrode-assemblies (MEAs) in a fuel cell stack. The method includes performing voltage cycling and humidification of the MEAs in the stack, including one or more temperature steps wherein current density of the stack is cycled within a predetermined range for each of the one or more temperature steps. The method also includes maintaining a fuel cell stack voltage within a predetermined range, and maintaining anode and cathode reactant flows at an approximate set-point during the current density cycling of the one or more temperature steps to break-in and humidify the MEAs in the stack so that the stack is able to operate at a predetermined threshold for a fuel cell stack voltage output capability.

Abstract: Fuel-cell membrane-subgasket assemblies may include an electrolyte membrane and a coated subgasket overlying the electrolyte membrane around a perimeter of the electrolyte membrane so as to define an active area inside the perimeter. The coated subgasket may comprise a subgasket body formed from a subgasket material. At least one side of the coated subgasket includes a subgasket coating layer containing or formed from a coating material such as metals, ceramics, polymers, polymer composites, or other hard coatings. Fuel-cell assemblies may include gas diffusion media, a bipolar plate, and a fuel-cell membrane-subgasket assembly having a coated subgasket. Fuel-cell stacks may include clamping plates, unipolar endplates, and a plurality of individual fuel-cell assemblies, at least one of which includes a fuel-cell membrane-subgasket assembly having a coated subgasket.

Abstract: Fuel-cell membrane-subgasket assemblies may include an electrolyte membrane and a coated subgasket overlying the electrolyte membrane around a perimeter of the electrolyte membrane so as to define an active area inside the perimeter. The coated subgasket may comprise a subgasket body formed from a subgasket material. At least one side of the coated subgasket includes a subgasket coating layer containing or formed from a coating material such as metals, ceramics, polymers, polymer composites, or other hard coatings. Fuel-cell assemblies may include gas diffusion media, a bipolar plate, and a fuel-cell membrane-subgasket assembly having a coated subgasket. Fuel-cell stacks may include clamping plates, unipolar endplates, and a plurality of individual fuel-cell assemblies, at least one of which includes a fuel-cell membrane-subgasket assembly having a coated subgasket.

Abstract: A system and method for breaking-in and humidifying membrane-electrode-assemblies (MEAs) in a fuel cell stack. The method includes performing voltage cycling and humidification of the MEAs in the stack, including one or more temperature steps wherein current density of the stack is cycled within a predetermined range for each of the one or more temperature steps. The method also includes maintaining a fuel cell stack voltage within a predetermined range, and maintaining anode and cathode reactant flows at an approximate set-point during the current density cycling of the one or more temperature steps to break-in and humidify the MEAs in the stack so that the stack is able to operate at a predetermined threshold for a fuel cell stack voltage output capability.

Abstract: An MEA for a fuel cell that employs multiple catalyst layers to reduce the hydrogen and/or oxygen partial pressure at the membrane so as to reduce the fluoride release rate from the membrane and reduce membrane degradation. An anode side multi-layer catalyst configuration is positioned at the anode side of the MEA membrane. The anode side multi-layer catalyst configuration includes an anode side under layer positioned against the membrane and including a catalyst, an anode side middle layer positioned against the anode side under layer and not including a catalyst and an anode side catalyst layer positioned against the anode side middle layer and opposite to the anode side under layer and including a catalyst, where the amount of catalyst in the anode side catalyst layer is greater than the amount of catalyst in the anode side under layer.

Abstract: A method for making a membrane electrode assembly includes the steps of providing a membrane electrode assembly including an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and depositing a peroxide decomposition catalyst in at least one position selected from the group consisting of the anode, the cathode, a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system.

Abstract: A membrane electrode assembly includes an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and a peroxide decomposition catalyst positioned in at least one position selected from the group consisting of a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system. The assembly components contain ionomer material which can be perfluorinated or non-perfluorinated, high temperature, hydrocarbon, and the like.

Abstract: A membrane electrode assembly includes a membrane layer, a cathode or anode catalyst layer adjacent to a surface of the membrane layer, an anode or cathode catalyst layer adjacent to an other surface of the membrane layer, an adhesive layer adjacent to the other surface of the membrane layer, wherein the adhesive layer abuts a surface of the anode or cathode catalyst layer, and a subgasket layer having an edge portion, wherein the subgasket layer is adjacent to a surface of the adhesive layer, wherein the cathode catalyst layer and anode catalyst layer extend along a length of the membrane layer relative to the edge portion of the subgasket layer, wherein the cathode or anode catalyst layer extends a greater length along the length of the membrane layer than the anode or cathode catalyst layer relative to the edge portion of the subgasket layer.

Abstract: An MEA for a fuel cell that employs multiple catalyst layers to reduce the hydrogen and/or oxygen partial pressure at the membrane so as to reduce the fluoride release rate from the membrane and reduce membrane degradation. An anode side multi-layer catalyst configuration is positioned at the anode side of the MEA membrane. The anode side multi-layer catalyst configuration includes an anode side under layer positioned against the membrane and including a catalyst, an anode side middle layer positioned against the anode side under layer and not including a catalyst and an anode side catalyst layer positioned against the anode side middle layer and opposite to the anode side under layer and including a catalyst, where the amount of catalyst in the anode side catalyst layer is greater than the amount of catalyst in the anode side under layer.

Abstract: A membrane electrode assembly includes an anode; a cathode; a membrane disposed between the anode and the cathode; and an extended catalyzed layer between the membrane and at least one electrode of the anode and the cathode. The extended catalyzed layer includes catalyst particles embedded in membrane material and preferably includes a first plurality of particles which are electrically connected to the at least one electrode. The extended catalyzed layer may further preferably have a second plurality of particles which are electrically disconnected from the at least one electrode.

Abstract: A decontamination procedure for a fuel cell power plant (10) includes operating the plant to produce electrical power for an operating period, and then terminating operation of the plant (10) for a decontamination period, and then, whenever optimal electrical production of a plant fuel cell (12) is reduced by at least 5% by contaminants adsorbed by fuel cell electrodes (24, 42), decontaminating the fuel cell (12) of the plant (10) during the decontamination period by oxidizing contaminants adsorbed by electrodes (24, 42) of the fuel cell. Oxidizing the contaminants may be accomplished by various steps including exposing the electrodes (24, 42) to flowing oxygen; to heated flowing oxygen; to a sequence of start-stop cycles; and, to varying controlled potentials.

Abstract: Methods for attaching a subgasket to an ionomer membrane, wherein the methods provide for the precise location of the subgasket relative to the other component edges of the fuel cell, such as the catalyst layers, so as provide the functionality required to extend the ionomer membrane life and prevent damage to the ionomer membrane during the assembly process.

Abstract: A membrane electrode assembly includes a membrane layer, a cathode or anode catalyst layer adjacent to a surface of the membrane layer, an anode or cathode catalyst layer adjacent to an other surface of the membrane layer, an adhesive layer adjacent to the other surface of the membrane layer, wherein the adhesive layer abuts a surface of the anode or cathode catalyst layer, and a subgasket layer having an edge portion, wherein the subgasket layer is adjacent to a surface of the adhesive layer, wherein the cathode catalyst layer and anode catalyst layer extend along a length of the membrane layer relative to the edge portion of the subgasket layer, wherein the cathode or anode catalyst layer extends a greater length along the length of the membrane layer than the anode or cathode catalyst layer relative to the edge portion of the subgasket layer.

Abstract: A membrane electrode assembly includes an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and a peroxide decomposition catalyst positioned in at least one position selected from the group consisting of the anode, the cathode, a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system.

Abstract: A method for making a membrane electrode assembly includes the steps of providing a membrane electrode assembly including an anode including a hydrogen oxidation catalyst; a cathode; a membrane disposed between the anode and the cathode; and depositing a peroxide decomposition catalyst in at least one position selected from the group consisting of the anode, the cathode, a layer between the anode and the membrane and a layer between the cathode and the membrane wherein the peroxide decomposition catalyst has selectivity when exposed to hydrogen peroxide toward reactions which form benign products from the hydrogen peroxide. The peroxide decomposition catalyst can also be positioned within the membrane. Also disclosed is a power-generating fuel cell system including such a membrane electrode assembly, and a process for operating such a fuel cell system.