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 carbon fiber woven fabric for use as a gas diffusion layer base material in a polymer electrolyte fuel cell has a surface that is smoothed and further optimized to inhibit non-uniform infiltration of a coating for water-repellent-layer formation, to provide an electrolyte membrane-electrode assembly suitable for operation under a high humidification condition. The gas diffusion layer base material may be a carbon fiber woven fabric, wherein a ratio of the area of gap portions where neither warp thread nor weft thread exists: (10/W−Y)(10/Z−X) to the area of portions where warp thread is crossing weft thread: XY mm2 is in the range of about {fraction (1/1500)} to about ⅕, where the carbon fiber woven fabric has a warp density of Z threads/cm, a weft density of W threads/cm, a warp thickness of X mm and a weft thickness of Y mm.

Abstract: The polymer electrolyte fuel cell of the present invention exhibits an excellent performance with an efficient electrode reaction; by providing a layer comprising an electroconductive fine particle between the catalytic reaction layer and the gas diffusion layer in the electrodes; by providing a hydrogen ion diffusion layer on at least either surface of the catalyst particle or the carrier, which carries the catalyst particle in the catalytic reaction layer; or by constituting the catalytic reaction layer with at least a catalyst comprising a hydrophilic carbon material with catalyst particles carried thereon and a water repellent carbon material.

Abstract: A polymer electrolyte membrane is put between two gas diffusion electrodes and the whole is pressed at a pressure until the bonding temperature is reached and then pressed at the bonding pressure not lower than the pressure applied in the preceding step, whereby MEAs are obtained. The state of bonding of the polymer electrolyte membrane and the gas diffusion electrodes to each other is improved. The internal resistance is reduced and the three-phase interface is made to assume a three-dimensional structure to enlarge the reaction area, and polymer electrolyte fuel cells with higher output can be materialized by using the MEA.

Abstract: A polymer electrolyte membrane is put between two gas diffusion electrodes and the whole is pressed at a pressure until the bonding temperature is reached and then pressed at the bonding pressure not lower than the pressure applied in the preceding step, whereby MEAs are obtained. The state of bonding of the polymer electrolyte membrane and the gas diffusion electrodes to each other is improved. The internal resistance is reduced and the three-phase interface is made to assume a three-dimensional structure to enlarge the reaction area, and polymer electrolyte fuel cells with higher output can be materialized by using the MEA.

Abstract: An electrode material, particularly a gas diffusion layer, for a fuel cell is provided which prevents electrode exfoliation during the manufacturing process by optimizing a water repellent material incorporated in the gas diffusion layer. The resulting electrode made from the gas diffusion layer has a high discharge performance at a low cost. This gas diffusion layer contacts a catalyst layer to form an electrode of the fuel cell layer, and the catalyst layer in turn contacts a polymer electrolyte membrane of the fuel cell. The gas diffusion layer contains a fibrillatable, water repellent material, and is subjected to heat treatment below the melting point of the water repellent material to fibrillate the material.

Abstract: A polymer electrolyte fuel cell which includes a pair of electrodes, a polymer electrolyte membrane interposed between the pair of the electrodes, a first conductive separator having a channel for supplying an oxidant gas to one of the electrodes therethrough, and a second conductive separator having a channel for supplying a fuel gas to the other of the electrodes therethrough, wherein at least one of the electrodes includes a porous catalyst layer formed on the surface of the polymer electrolyte membrane, or formed on the surface of a porous conductive base.

Abstract: Disclosed is a polymer electrolyte fuel cell having an improved separator plate. The fuel cell comprises a solid polymer electrolyte membrane; an anode and a cathode sandwiching the solid polymer electrolyte membrane therebetween; an anode-side conductive separator plate having a gas flow path for supplying a fuel gas to the anode; and a cathode-side conductive separator plate having a gas flow path for supplying an oxidant gas to the cathode, wherein each of the anode-side and cathode-side conductive separator plates is composed of a metal and a conductive coat which has resistance to oxidation and covers a surface of the metal. Alternatively, the above-mentioned separator plates are formed of a metal and a coat having resistance to oxidation and have roughened surfaces with recessions and protrusions, and portions of a top surface of the protruding portions, which lack the coat, are electrically connected to an electrode.

Abstract: The specification discloses a fuel cell comprising stacked unit cells, each of the unit cells including a pair of electrodes having a catalytic reaction layer and a gas diffusion layer, an electrolyte layer disposed between the pair of electrodes, a separator having a flow path for supplying a fuel gas to one electrode and a separator having a flow path for supplying an oxidant gas to the other electrode, the separators being placed on the outer side of the electrodes and the unit cells being stacked with the separators placed therebetween, wherein at least the catalytic reaction layer, the gas diffusion layer or the flow path has water-repelling properties. Thereby, a fuel cell having a superior cell performance is obtained.

Abstract: The invention provides a fuel cell system that is free from troubles due to contaminant ions by controlling the concentration of contaminant ions in cooling water. The fuel cell system comprises a fuel cell stack and a means for controlling the cell temperature by circulating a liquid coolant in the fuel cell stack or bringing it in contact with the fuel cell stack, the fuel cell stack comprising a plurality of unit cells that are laid one upon another, each of the unit cells comprising a hydrogen ion-conductive electrolyte membrane, a pair of gas diffusion electrodes which sandwich the electrolyte membrane, an anode-side conductive separator plate having a gas flow path for supplying a fuel gas to one of the electrodes, and a cathode-side conductive separator plate having a gas flow path for supplying an oxidant gas to the other of the electrodes, wherein a material adsorbing or absorbing ions is provided on a portion of the fuel cell system to come in contact with the liquid coolant.

Abstract: An aim of the invention is to provide a fuel cell power generation system which can operate in a reduced space to reduce the initial cost and the running cost without deteriorating the performance. In a fuel cell power generation system comprising a fuel cell having an anode, a cathode and a polymer electrolyte membrane, a fuel gas feed pipe for supplying a fuel gas into the anode, an oxidant gas feed pipe for supplying an oxidant gas into the cathode, a reforming unit connected to the fuel gas feed pipe for reforming a raw material gas, a heating unit for heating the reforming unit, a raw material gas supplying unit for supplying the raw material gas into the reforming unit, a water supplying unit for supplying water into the reforming unit, and an air supplying unit for supplying air into the reforming unit, water is introduced into at least one selected from the fuel gas feed pipe, the oxidant gas feed pipe, the cathode and the anode to purge gases retained in the system.

Abstract: A polymer electrolyte fuel cell comprising: a hydrogen ion-conductive polymer electrolyte membrane; an anode and a cathode with the electrolyte membrane interposed therebetween; an anode-side conductive separator having a gas flow channel for supply of a fuel gas to the anode; and a cathode-side conductive separator having a gas flow channel for supply of an oxidant gas to the cathode, wherein each of the anode and the cathode comprises at least a catalyst layer in contact with the electrolyte membrane and a gas diffusion layer in contact with the catalyst layer and the separator, and at least one of the anode and the cathode contains a compound represented by the formula (I):

Abstract: To improve the performance of a catalyst layer of a fuel cell electrode, the weight ratio of a hydrogen ion conductive polymer electrolyte and electroconductive carbon particles in the catalyst layer is controlled to satisfy the formula (1): Y=a·logX−b+c, where log represents natural logarithm, X represents the specific surface area of the electroconductive carbon particles (m2/g), Y=(the weight of the hydrogen ion conductive polymer electrolyte)/(the weight of the electroconductive carbon particles), a=0.216, c=±0.300, b=0.421 at an air electrode and b=0.221 at an fuel electrode.

Abstract: In order to obtain an electrolyte membrane-electrode assembly using a thin electrolyte membrane, the present invention provides a production method of an electrolyte membrane-electrode assembly comprising: a step of forming a hydrogen ion-conductive polymer electrolyte membrane on a base material; a treatment step of reducing adhesion force between the base material and the hydrogen ion-conductive polymer electrolyte membrane; a step of separating and removing the base material; and a step of bonding a catalyst layer and a gas diffusion layer onto the hydrogen ion-conductive polymer electrolyte membrane, and, in order to obtain an electrolyte membrane-electrode assembly which has a catalyst without clogging and is excellent in electrode characteristics, the present invention provides a production method of an electrolyte membrane-electrode assembly comprising: a step of bonding a hydrogen ion-conductive polymer electrolyte membrane and a catalyst layer via a coating layer; a step of removing the coating layer

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 polymer electrolyte fuel cell comprising an anode, a cathode, a polymer electrolyte membrane interposed between the anode and the cathode, an anode-side separator plate having a gas flow path to supply fuel gas to the anode and a cathode-side separator plate having a gas flow path to supply oxidant gas to the cathode. Each of the anode and the cathode comprises a catalyst layer in contact with the polymer electrolyte membrane, an electrode supporting material having gas permeability and electronic conductivity, and a water repellent layer interposed between the catalyst layer and the electrode supporting material. The water repellent layer has through holes through which the catalyst layer and the electrode supporting material are electrically connected.

Abstract: A method for preparing a substrate for a flexible print wiring board having a polyimide based resin layer wherein a solution of a polyimide based resin precursor is directly applied on an electrically conducting material to form a polyimide based resin precursor layer and then the precursor layer is cured by heating to prepare a polyimide based resin layer, characterized in that a solution of a polyimide based resin precursor B, which is one of solutions of two types of polyimide based resin precursors, is directly applied on an electrically conducting material and then, on the resultant layer is applied a solution of a polyimide based resin precursor A which allows resolving the residual strain generated in the polyimide based resin formed by the curing of the above polyimide based resin precursor B.

Abstract: A method of producing an electrode having a high performance in a simple and convenient manner which does not require the use of any of the medium, surfactant and pore-producing agent is disclosed. In the disclosed method, a layer including a catalyst powder is formed on a surface of a polymer electrolyte film or a porous conductive electrode substrate by supplying an electrostatically-charged catalyst powder to the polymer electrolyte film or the porous conductive electrode substrate. Alternatively, a layer including a catalyst powder is formed on a surface of a polymer electrolyte film or a porous conductive electrode substrate by spraying the catalyst powder on the surface of the polymer electrolyte film or the porous conductive electrode substrate together with a carrier gas, thereby to cause the catalyst powder to adhere to the surface.

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: Disclosed is a fuel cell comprising: a hydrogen-ion conductive polymer electrolyte membrane; a pair of electrodes sandwiching the hydrogen-ion conductive polymer electrolyte membrane; a first separator plate having a gas flow path for supplying a fuel gas to one of the electrodes; and a second separator plate having a gas flow path for supplying an oxidant gas to the other of the electrodes, wherein each of the electrodes has an electrode catalyst layer comprising at least a conductive carbon particle carrying an electrode catalyst particle and a hydrogen-ion conductive polymer electrolyte, the electrode catalyst layer being in contact with the hydrogen-ion conductive polymer electrolyte membrane, and at least one of the electrodes comprises a catalyst for trapping the fuel gas or the oxidant gas which has passed through the hydrogen-ion conductive polymer electrolyte membrane from the other electrode toward the electrode catalyst layer of the one of the electrodes.