Abstract: A fuel cell power system includes a fuel cell stack prepared by stacking a plurality of electric cells, each having an anode and a cathode with an electrolyte therebetween, a fuel supply line and an oxidant supply line that respectively supply a fuel and an oxidant to the fuel cell stack, and a fuel exhaust line and an oxidant exhaust line that respectively exhaust the fuel and oxidant supplied to the fuel cell stack.

Abstract: In order to prevent an electrolyte membrane from being broken, and make an assembling steps of a cell easy, in a fuel cell provided with a membrane electrode complex in which catalyst layers are respectively arranged on both surfaces of a electrolyte membrane, first and second gas diffusion layers which are arranged on both surfaces of the electrode complex, separators for respectively supplying reaction gas to the first and second gas diffusion layers, and a gasket for sealing the reaction gas, the gasket is formed on a surface of the gas diffusion layer so as to oppose to the separator, at least the gasket forming portion of the gas diffusion layer has a lower void content than the portion in contact with the catalyst layer, and the gasket arranged in the first and second gas diffusion layers is integrally formed at least via a through hole passing through the first and second gas diffusion layers.

Abstract: In order to prevent an electrolyte membrane from being broken, and make an assembling steps of a cell easy, in a fuel cell provided with a membrane electrode complex in which catalyst layers are respectively arranged on both surfaces of a electrolyte membrane, first and second gas diffusion layers which are arranged on both surfaces of the electrode complex, separators for respectively supplying reaction gas to the first and second gas diffusion layers, and a gasket for sealing the reaction gas, the gasket is formed on a surface of the gas diffusion layer so as to oppose to the separator, at least the gasket forming portion of the gas diffusion layer has a lower void content than the portion in contact with the catalyst layer, and the gasket arranged in the first and second gas diffusion layers is integrally formed at least via a through hole passing through the first and second gas diffusion layers.

Abstract: A fuel cell power system includes a fuel cell stack prepared by stacking a plurality of electric cells, each having an anode and a cathode with an electrolyte therebetween, a fuel supply line and an oxidant supply line that respectively supply a fuel and an oxidant to the fuel cell stack, and a fuel exhaust line and an oxidant exhaust line that respectively exhaust the fuel and oxidant supplied to the fuel cell stack.

Abstract: A method for operating a fuel cell power plant. The fuel cell can include a reactant passage (22) with an upstream portion and a downstream portion for providing reactant to an electrode (16, 18), at least one liquid passage (24), and a plate (20) made from a porous material that is liquid permeable and conductive. The porous material separates the reactant passage and the liquid passage. A pressure profile is controlled to provide a positive pressure difference in the upstream portion and a negative pressure difference in the downstream portion. A positive pressure difference is one where the liquid pressure is higher than that of the reactant. A negative pressure difference is one where the liquid pressure is less than that of the reactant. The pressure profile can be used to provide enhanced humidification of the reactant in the upstream portion and effective liquid water removal in the downstream portion to maximize both the performance and the life of the fuel cell.

Abstract: In order to prevent an electrolyte membrane from being broken, and make an assembling steps of a cell easy, in a fuel cell provided with a membrane electrode complex in which catalyst layers are respectively arranged on both surfaces of a electrolyte membrane, first and second gas diffusion layers which are arranged on both surfaces of the electrode complex, separators for respectively supplying reaction gas to the first and second gas diffusion layers, and a gasket for sealing the reaction gas, the gasket is formed on a surface of the gas diffusion layer so as to oppose to the separator, at least the gasket forming portion of the gas diffusion layer has a lower void content than the portion in contact with the catalyst layer, and the gasket arranged in the first and second gas diffusion layers is integrally formed at least via a through hole passing through the first and second gas diffusion layers.

Abstract: In order to prevent an electrolyte membrane from being broken, and make an assembling steps of a cell easy, in a fuel cell provided with a membrane electrode complex in which catalyst layers are respectively arranged on both surfaces of a electrolyte membrane, first and second gas diffusion layers which are arranged on both surfaces of the electrode complex, separators for respectively supplying reaction gas to the first and second gas diffusion layers, and a gasket for sealing the reaction gas, the gasket is formed on a surface of the gas diffusion layer so as to oppose to the separator, at least the gasket forming portion of the gas diffusion layer has a lower void content than the portion in contact with the catalyst layer, and the gasket arranged in the first and second gas diffusion layers is integrally formed at least via a through hole passing through the first and second gas diffusion layers.

Abstract: A fuel cell is provided, in which the generation of hydrogen, which is one cause of degradation of the cell characteristics, is controlled, thus preventing the degradation of the electrolyte member and maintaining stable cell characteristics for a long time. The fuel cell has a fuel pole, an oxidizer pole opposed to the fuel pole, and an electrolyte member arranged between the fuel pole and the oxidizer pole and having ion conductivity. The electrolyte member comprises three layers, i.e., a first electrolyte layer and two second electrolyte layers. The first electrolyte layer is interposed between the second electrolyte layers. The second electrolyte layer contacts the fuel pole and the oxidizer pole and is a layer that prevents the passage of oxygen from the oxidizer pole to the fuel pole. The second electrolyte layer contains catalyst.

Abstract: A fuel cell stack comprises membrane electrode assemblies (3) in which gas diffusion electrodes (2a,2b) are arranged on both sides of an ion exchange membrane (1) and a reactant gas supply separators (5) interposed between the membrane electrode assemblies (3). The reactant gas supply separators (5) each has a first surface having first reactant gas supply grooves (9a) for supplying first reactant gas, a second surface having second reactant gas supply grooves (9b) for supplying an second reactant gas, and water supply means for supplying water to the first reactant gas supply grooves (9a). The water supply means has a water supply grooves (15) for introducing water from a water supply manifold (14) disposed on the second surface, communication holes (16) for communication of the second surface with the first surface, and a buffer section (17) having a porous body (20) for uniformly distributing water from the water supply grooves (15) to the communication holes (16).

Abstract: In a polymer electrolyte fuel cell stack using a latent heat cooling system, a plurality of first reactant gas flow paths formed in one plate surface of each separator are made substantially linear in the vertical direction, and an arrangement capable of supplying water to the first reactant gas flow paths includes a water manifold formed to extend through the separator, a water supply path branched from the water manifold and horizontally formed in a surface in which second reactant gas flow paths are formed, and communication holes horizontally formed in a first reactant gas flow path introducing portion to allow the water supply path to communicate with the first reactant gas flow paths, and present above the lowermost portion in the vertical direction of the water manifold. With this arrangement, stable power generation can be performed regardless of, e.g., the stack installation angle or vibrations.

Abstract: A method for operating a fuel cell power plant. The fuel cell can include a reactant passage (22) with an upstream portion and a downstream portion for providing reactant to an electrode (16, 18), at least one liquid passage (24), and a plate (20) made from a porous material that is liquid permeable and conductive. The porous material separates the reactant passage and the liquid passage. A pressure profile is controlled to provide a positive pressure difference in the upstream portion and a negative pressure difference in the downstream portion. A positive pressure difference is one where the liquid pressure is higher than that of the reactant. A negative pressure difference is one where the liquid pressure is less than that of the reactant. The pressure profile can be used to provide enhanced humidification of the reactant in the upstream portion and effective liquid water removal in the downstream portion to maximize both the performance and the life of the fuel cell.

Abstract: A solid polymer fuel cell having a structure in which a film electrode composite having gas diffusion electrodes disposed on both surfaces of a solid polymer film and separators having gas channels to feed at least either a fuel gas or an oxidant gas to the electrodes are laminated repeatedly in such a manner that they contact each other, wherein the separators each comprise a carbon resin composite material and an expansion graphite layer, on at least one surface of the material, pits and projections to form the gas channels are formed, and the layer is formed on the surfaces of the material including the pits and the projections.

Abstract: In a polymer electrolyte fuel cell stack using a latent heat cooling system, a plurality of first reactant gas flow paths formed in one plate surface of each separator are made substantially linear in the vertical direction, and an arrangement capable of supplying water to the first reactant gas flow paths includes a water manifold formed to extend through the separator, a water supply path branched from the water manifold and horizontally formed in a surface in which second reactant gas flow paths are formed, and communication holes horizontally formed in a first reactant gas flow path introducing portion to allow the water supply path to communicate with the first reactant gas flow paths, and present above the lowermost portion in the vertical direction of the water manifold. With this arrangement, stable power generation can be performed regardless of, e.g., the stack installation angle or vibrations.

Abstract: In order to prevent an electrolyte membrane from being broken, and make an assembling steps of a cell easy, in a fuel cell provided with a membrane electrode complex in which catalyst layers are respectively arranged on both surfaces of a electrolyte membrane, first and second gas diffusion layers which are arranged on both surfaces of the electrode complex, separators for respectively supplying reaction gas to the first and second gas diffusion layers, and a gasket for sealing the reaction gas, the gasket is formed on a surface of the gas diffusion layer so as to oppose to the separator, at least the gasket forming portion of the gas diffusion layer has a lower void content than the portion in contact with the catalyst layer, and the gasket arranged in the first and second gas diffusion layers is integrally formed at least via a through hole passing through the first and second gas diffusion layers.

Abstract: To render a polymer electrolyte fuel cell and a power-generating system with polymer electrolyte fuel cells, simple, compact and lightweight, the following measures are taken. A plurality of reactant-gas supplying separator are provided, each on at least one surface of each unit cell. Each reactant-gas supplying separator has fuel-gas supplying passages such as grooves in one surface, and oxidizer-gas supplying passages such as grooves in the other surface. Each unit cell comprises a catalyst layer and an electrically conductive, porous water-repellant layer provided at least between the catalyst layer and the grooves. The system comprises water-supplying means for supplying water in liquid state to a fuel-gas inlet section and a water-amount control means for controlling the amount of water to be supplied to the fuel-gas inlet section.

Abstract: A method for operating a fuel cell power plant. The fuel cell can include a reactant passage (22) with an upstream portion and a downstream portion for providing reactant to an electrolyte (14), at least one liquid passage (24), and a plate (20) made from a porous material that is liquid permeable and conductive. The porous material separates the reactant passage and the liquid passage. A pressure profile is controlled to provide a positive pressure difference in the upstream portion and a negative pressure difference in the downstream portion. A positive pressure difference is one where the liquid pressure is higher than that of the reactant. A negative pressure difference is one where the liquid pressure is less than that of the reactant. The pressure profile can be used to provide enhanced humidification of the reactant in the upstream portion and effective liquid water removal in the downstream portion to maximize both the performance and the life of the fuel cell.

Abstract: A solid polymer type fuel cell system according to the present invention has a heat source of exhaust fluid from an electricity generation unit 23 in condensed heat exchangers 38, 40 in a heat recovery unit 19 and supply water from a water supply unit 66 as a heat source to be heated to a hot water through heat-exchanging process. The fuel cell system comprises a hot water supply unit 41 for supplying the hot water to a heat utilization section, gas-liquid separator 30 for preliminarily mixing the drain water generated during the heat-exchanging process to the fuel to be supplied to a fuel reforming unit 22, and a circulation path 45 for circulating the water to a cell body 32 of the electricity generation unit to carry out the heat-exchanging and supplying the hot water to the heat utilization section.

Abstract: A polymer electrolyte fuel cells system wherein a reacted gas that has been passed through a cell stack is enabled to be contacted with an unreacted gas to be passed through the cell stack, thereby carrying out a temperature/humidity exchange for the purpose of preventing the drying of a solid polymer electrolyte membrane. The temperature of the unreacted gas is made lower than the temperature of the reacted gas.

Abstract: A solid polymer fuel cell having a structure in which a film electrode composite having gas diffusion electrodes disposed on both surfaces of a solid polymer film and separators having gas channels to feed at least either a fuel gas or an oxidant gas to the electrodes are laminated repeatedly in such a manner that they contact each other, wherein the separators each comprise a carbon resin composite material and an expansion graphite layer, on at least one surface of the material, pits and projections to form the gas channels are formed, and the layer is formed on the surfaces of the material including the pits and the projections.

Abstract: A fuel cell system comprising a fuel cell stack and a fuel reformer for reforming a fuel and supplying a reformed fuel to the fuel cell stack, further comprising a total enthalpy heat exchanger for exchanging heat and moisture between a reacted gas and an unreacted gas from the fuel cell stack, a separator for separating moisture from the fuel gas fed from the fuel cell stack or from an oxidant gas, and a mixer for mixing part of the moisture separated by the separator with a medium having a freezing point of 0° C. or less.