Abstract: In a polymer electrolyte fuel cell including a hydrogen ion conductive polymer electrolyte membrane; a pair of electrodes composed of catalyst layers sandwiching the hydrogen ion conductive polymer electrolyte membrane between them and gas diffusion layers in contact with the catalyst layers; a conductive separator plate having a gas flow channel for supplying a fuel gas to one of the electrodes; and a conductive separator plate having a gas flow channel for supplying an oxidant gas to the other electrode, in order to bring a hydrogen ion conductive polymer electrolyte and a catalyst metal of the catalyst layers containing the hydrogen ion conductive polymer electrolyte and conductive carbon particles carrying the catalyst metal sufficiently and uniformly into contact with each other, the polymer electrolyte is provided in pores of an agglomerate structure of the conductive carbon particles. Consequently, the reaction area inside the electrodes is increased, and higher performance is exhibited.

Abstract: A fuel cell component includes an electrolyte membrane and insert members disposed within the electrolyte membrane. The insert members are arranged to provide compression resistance of the assembly of the insert members and electrolyte membrane. Creep resistance of the assembly of the insert members and electrolyte membrane is greater than a creep resistance of the electrolyte membrane alone.

Abstract: An operation method is provided for a polymer electrolyte fuel cell in an optimum operating condition by regulating the cell by a function represented by a gas flow rate and the difference between a saturated steam pressure and an actual steam pressure, by regulating an in-plane temperature distribution obtained by a cooling water flow direction and by the regulation of a cooling water inlet temperature and a cooling water flow amount; a gas supply amount; a supplied moisture amount; and a current density.

Abstract: A polymer electrolyte fuel cell is provided comprising: a hydrogen ion conductive polymer electrolyte membrane; an anode and a cathode sandwiching the hydrogen ion conductive polymer electrolyte membrane; an anode side electroconductive separator having a gas channel for supplying a fuel gas to the anode; a cathode side electroconductive separator having a gas channel for supplying an oxidant gas to the cathode; characterized in that the anode and the cathode comprise a gas diffusion layer and a catalyst layer formed on the gas diffusion layer at the side in contact with the hydrogen ion conductive polymer electrolyte membrane, the catalyst layer has catalyst particles and a hydrogen ion conductive polymer electrolyte, and at least either of hydrogen ion conductivity and gas permeability of at least either of the anode and the cathode varies in a thickness direction of the anode or the cathode.

Abstract: Methods are provided for easily obtaining a high performance electrode without using an organic solvent for making an ink of an electrode catalyst or a surfactant for making an ink of a water repellent carbon material. The methods of manufacturing an electrode for a polymer electrolyte fuel cell comprise (a) a step of adhering a polymer electrolyte or a water repellent material to fine electrically conductive particles, and granulating the electrically conductive particles to obtain multinary granules, and (b) a step of depositing the multinary granules in layer form to obtain a catalyst layer or a water repellent layer of an electrode. Apparatus for manufacturing the electrodes, as well as polymer electrolyte fuel cells using the electrodes are also provided.

Abstract: A polymer-electrolyte fuel cell having: an electrolyte membrane-electrode assembly having a polymer-electrolyte membrane and a pair of gas-diffusion electrodes sandwiching the polymer-electrolyte membrane; a first electroconductive separator having a gas channel for supplying an oxidant gas to one of the gas-diffusion electrodes of said pair; and a second electroconductive separator having a gas channel for supplying a fuel gas to the other of the gas-diffusion electrodes of the pair. The polymer-electrolyte fuel cell is characterized in that: at least one of the first and second electroconductive separators has a metal substrate and an electroconductive resin layer on the substrate and contacting the electrolyte membrane-electrode assembly; and the electroconductive resin layer has a resin having water-repellant or basic radicals, and an electroconductive particulate substance which has a carbon powder of a specific surface area of less than 100 m2/g.

Abstract: It has been difficult to keep the voltage of a polymer electrolyte fuel cell stable for a long period of time because uniform water content control over the plane of the membrane-electrode assembly is impossible. A gas diffusion electrode is produced by forming a conductive polymer layer composed of conductive particles and a polymer material on a porous material composed of carbon fiber, and forming a catalyst layer composed of platinum-carried carbon particles on the plane of the conductive polymer layer. The conductive polymer layer is composed of conductive particles different in particle size, and the content of the conductive particles having the smaller particle size is decreased from one end towards the other end of the gas diffusion electrode.

Abstract: Methods are provided for easily obtaining a high performance electrode without using an organic solvent for making an ink of an electrode catalyst or a surfactant for making an ink of a water repellent carbon material. The methods of manufacturing an electrode for a polymer electrolyte fuel cell comprise (a) a step of adhering a polymer electrolyte or a water repellent material to fine electrically conductive particles, and granulating the electrically conductive particles to obtain multinary granules, and (b) a step of depositing the multinary granules in layer form to obtain a catalyst layer or a water repellent layer of an electrode. Apparatus for manufacturing the electrodes, as well as polymer electrolyte fuel cells using the electrodes are also provided.

Abstract: A polymer electrolyte fuel cell is provided comprising: a hydrogen ion conductive polymer electrolyte membrane; an anode and a cathode sandwiching the hydrogen ion conductive polymer electrolyte membrane; an anode side electroconductive separator having a gas channel for supplying a fuel gas to the anode; a cathode side electroconductive separator having a gas channel for supplying an oxidant gas to the cathode; characterized in that the anode and the cathode comprise a gas diffusion layer and a catalyst layer formed on the gas diffusion layer at the side in contact with the hydrogen ion conductive polymer electrolyte membrane, the catalyst layer has catalyst particles and a hydrogen ion conductive polymer electrolyte, and at least either of hydrogen ion conductivity and gas permeability of at least either of the anode and the cathode varies in a thickness direction of the anode or the cathode.

Abstract: The present invention provides a gas diffusion layer for a fuel cell which has proper rigidity, is easy to handle and contributes to the improvement of the productivity of fuel cells. A method for producing a gas diffusion layer for a fuel cell including a first step of: impregnating a conductive porous substrate made of a conductive carbon fiber cloth or conductive carbon fiber felt with a first dispersion containing a first fluorocarbon resin having thermoplasticity; and baking the first conductive porous substrate at a first baking temperature of not less than the melting point of the first fluorocarbon resin and less than the decomposition temperature of the first fluorocarbon resin to enhance the rigidity of the conductive porous substrate.

Abstract: The present invention relates to a polymer electrolyte fuel cell comprising: an electrolyte membrane-electrode assembly including an anode, a cathode and a polymer electrolyte membrane interposed therebetween; an anode-side conductive separator plate having a gas flow channel for supplying a fuel gas to the anode; and a cathode-side conductive separator plate having a gas flow channel for supplying an oxidant gas to the cathode. A conductive separator plate made of carbon has poor wettability with water. This has posed the disadvantage that variations in performance are induced by nonuniform gas distribution among cells due to the accumulation of product water or humidifying water in the gas flow channel on the surface of the separator plate. The present invention employs a conductive separator plate comprising a conductive carbon having a hydrophilic functional group, at least in a portion of the gas flow channels, thereby preventing water from accumulating in the gas flow channels.

Abstract: A polymer electrolyte fuel cell comprises a separator plate having a gas channel for supplying an oxidant gas or a fuel gas to an electrode, said separator plate comprising a metal plate, a conductive film formed on the surface of the metal plate, and a diffused layer resulting from diffusion of a material of the conductive film formed between the metal plate and the conductive film. The fuel cell produces stable output free from corrosion or dissolution of the metal plate even in a long-term operation.

Abstract: A fuel cell includes an electrolyte membrane, a pair of anode-side and cathode-side catalyst layers, a pair of an anode gas diffusion layer and a cathode gas diffusion layer, and a pair of an anode-side separator and a cathode-side separator. Also adjusted in the fuel cell is at least one of a fine pore diameter and a content of a water repellent agent in the anode gas diffusion layer and the cathode gas diffusion layer, so as to satisfy the following equation (1): ?0.07?(Ya?Xa)/((Ya?Xa)+(Yc?Xc))?0.15??(1) wherein Xa represents a water feeding amount in the fuel gas thus fed, Ya represents a water discharging amount in the discharged fuel gas, Xc represents a water feeding amount in the oxidizing gas thus fed, and Yc represents a water discharging amount in the discharged oxidizing gas.

Abstract: The present invention restores the performance of a fuel cell by: operating the cell in a loaded current mode different from that of a normal operation for a predetermined time; supplying an oxidant gas and a fuel gas to an anode and a cathode respectively and outputting a current from a cell body with the polarity being inverted; supplying a pressurized gas to at least one of the cathode and anode in an amount not less than 1.5 times as much as that in the normal operation or supplying oxygen to the cathode; or injecting a cleaning solution into the cathode and anode through a gas flow path. Consequently, it is possible to effectively restore a degraded performance of a polymer electrolyte fuel cell caused by a long operation.

Abstract: A polymer electrolyte fuel cell stack that includes a cell laminate having a plurality of unit cells, which are laid one upon another and each of which includes a polymer electrolyte membrane, a pair of electrodes arranged across the polymer electrolyte membrane and having respective catalytic reaction layers, a separator having means for feeding a supply of fuel gas containing hydrogen gas to one of the electrodes, another separator having means for feeding a supply of oxidant gas to the other of the electrodes, and a manifold for feeding the supply of fuel gas or the supply of oxidant gas to the respective electrode and disposed on a side face of each unit cell. In the polymer electrolyte fuel cell stack, a sealing portion is disposed at least in the vicinity of each electrode. The polymer electrolyte fuel cell stack has excellent durability and productivity.

Abstract: A method for producing a membrane electrode assembly 1 for solid polymer electrolyte fuel cell, the membrane electrode assembly 1 including a solid polymer electrolyte membrane 2 comprising an ion exchange membrane, a first electrode 3 having a first catalyst layer 31, and a second electrode 4 having a second catalyst layer 41, the first electrode 3 and the second electrode 4 being disposed so as to be opposed to each other via the ion exchange membrane, the method including: applying a coating solution containing a catalyst onto a base film 101 to form a first catalyst layer 31; applying a coating solution containing an ion exchange resin dissolved or dispersed in a liquid onto the first catalyst layer 31 to form an ion exchange membrane; then applying a coating solution containing a catalyst onto the ion exchange membrane to form a second catalyst layer 41; and finally, peeling off the base film 101 from a resulting laminate.

Abstract: A polymer electrolyte fuel cell stack that includes a cell laminate having a plurality of unit cells, which are laid one upon another and each of which includes a polymer electrolyte membrane, a pair of electrodes arranged across the polymer electrolyte membrane and having respective catalytic reaction layers, a separator having means for feeding a supply of fuel gas containing hydrogen gas to one of the electrodes, another separator having means for feeding a supply of oxidant gas to the other of the electrodes, and a manifold for feeding the supply of fuel gas or the supply of oxidant gas to the respective electrode and disposed on a side face of each unit cell. In the polymer electrolyte fuel cell stack, a sealing portion is disposed at least in the vicinity of each electrode. The polymer electrolyte fuel cell stack has excellent durability and productivity.

Abstract: A fuel cell power generator is described which is capable of maintaining the electroconductivity of the cooling medium at a low level for a long period of time thereby preventing the metal components contacting the cooling medium from corroding, and functioning without causing any harm to power generation. Embodiments include a fuel cell power generator having a fuel cell, a cooling medium pipe, a heat exchanger and a means for circulating cooling the medium. These elements are arranged so that the formation of a conductive network electrically connecting the fuel cell, the pipe, the heat exchanger and the circulating means is prevented.

Abstract: The present invention discloses an operation method for a polymer electrolyte fuel cell in an optimum operating condition by regulating the cell by a function represented by a gas flow rate and the difference between a saturated steam pressure and an actual steam pressure, by regulating an in-plane temperature distribution obtained by a cooling water flow direction and by the regulations of a cooling water inlet temperature and a cooling water flow amount; a gas supply amount; a supplied moisture amount; and a current density.

Abstract: An operation method is provided for a polymer electrolyte fuel cell in an optimum operating condition by regulating the cell by a function represented by a gas flow rate and the difference between a saturated steam pressure and an actual steam pressure, by regulating an in-plane temperature distribution obtained by a cooling water flow direction and by the regulation of a cooling water inlet temperature and a cooling water flow amount; a gas supply amount; a supplied moisture amount; and a current density.