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.

Abstract: A polymer electrolyte fuel cell of the present invention includes conductive separator plates comprising molded plates of a composition comprising a binder, conductive carbon particles whose average particle diameter is not less than 50 &mgr;m and not more than ⅓ of the thickness of the thinnest portion of the conductive separator plate, and at least one of conductive carbon fine particles and micro-diameter carbon fibers. The separator plates do not require conventional cutting processes for gas flow channels, etc., and can be easily mass produced by injection molding and achieve a reduction in the cost.

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.

Abstract: A polymer electrolyte fuel cell comprising: a plurality of conductive separator plates, each comprising a corrugated metal plate; an electrolyte membrane-electrode assembly inserted between the separator plates, the electrolyte membrane-electrode assembly including a hydrogen-ion conductive polymer electrolyte membrane having its periphery covered with a gasket, an anode attached to one side of the electrolyte membrane, and a cathode attached to the other side of the electrolyte membrane; and gas charge and discharge means for charging and discharging a fuel gas and an oxidant gas to and from the anode and the cathode, respectively, wherein the gas charge and discharge means charges and discharges the fuel gas to and from the anode through the grooves on one side of the corrugated metal plate and charges and discharges the oxidant gas to and from the cathode through the grooves on the other side of the corrugated metal plate.

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: To provide a polyelectrolyte type fuel cell including single cells having a pair of electrodes placed at positions sandwiching a hydrogen ion polyelectrolyte membrane and supplying/exhausting means of supplying/exhausting a fuel gas to/from one of the electrodes and supplying/exhausting an oxidizer gas to/from the other of the electrodes, which are stacked one atop another through a conductive separator and have circulating means of circulating a cooling medium of cooling the electrodes, characterized in that at least one selected from among an amount of the fuel gas supplied, an amount of the fuel gas humidified, an amount of the oxidizer gas supplied, an amount of the oxidizer gas humidified, a flow rate or temperature of the cooling medium or an output current value of the polyelectrolyte type fuel cell is adjusted in such a way that an inlet temperature (Twin (° C.)) of the cooling medium or an outlet temperature of the cooling medium (Twout (° C.)) becomes 60° C. or higher.

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: 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 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: 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 a polymer electrolyte fuel cell of the present invention, at least one of electrodes comprises conductive carbon carrying a platinum group metal catalyst, conductive carbon carrying no catalyst metal and a hydrogen ion-conductive polymer electrolyte. The preferable amount of the conductive carbon carrying no catalyst metal is equivalent to 5 to 50 wt % of the conductive carbon carrying the catalyst metal. Incorporation of the conductive carbon carrying no catalyst metal to the catalyst layer enables reduction in potential concentration on part of electron conduction channels in an electrode, whereby an electrode for a polymer electrolyte fuel cell having an excellent life characteristic can be provided.

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: A porous supporting carbon body of a gas diffusion layer is provided with a larger number of smaller pores at its catalyst layer side and a smaller number of larger pores at the other side, particularly with an appropriate distribution of finer mesh at its catalyst layer side and coarser mesh at the other side. As a result, a high performance polymer electrolyte fuel cell is obtained in which water generated at the catalyst layer is quickly sucked out to the gas diffusion layer, and is evaporated at the gas diffusion layer to be effectively exhausted to outside the fuel cell, so that excessive water can be prevented from retaining in the gas diffusion electrode, with the polymer electrolyte membrane being maintained at an appropriately wet condition.

Abstract: For the purpose of efficiently producing an electrolyte membrane electrode assembly which is excellent in the bond strength between layers and the like, a method for producing an electrolyte membrane electrode assembly is provided which conducts either sequentially or simultaneously the step of injecting an electrolyte ink to form an electrolyte layer and the step of injecting a catalyst layer ink to form a catalyst layer on the electrolyte layer.

Abstract: A polymer electrolyte fuel cell of the present invention includes a hydrogen ion-conductive polymer electrolyte membrane, an anode and a cathode sandwiching the hydrogen ion-conductive polymer electrolyte membrane, 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.

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: In a molten carbonate fuel cell having an anode a cathode which are both porous gas-diffusion electrodes, and an electrolyte making contact with both the electrodes, the cathode includes a metal oxide represented by the formula Li.sub.x Ni.sub.1-x O (0.05.ltoreq..times.<0.5, preferably 0.05.ltoreq..times.<0.2), and at least one of the cathode and electrolyte contains an alkaline earth metal carbonate. The disclosed cathode has a small solubility in the electrolyte of alkali metal carbonate and a long service life.

Abstract: A vehicle using hydrogen absorbing alloys includes: a plurality of hydrogen absorbing alloy storing vessels for independently storing a plurality of hydrogen absorbing alloys with a different hydrogen equilibrium decomposition pressure; a connecting section for passing hydrogen to and fro among the plurality of hydrogen absorbing alloy storing vessels; and a heating section for heating a low pressure hydrogen absorbing alloy which has the lowest hydrogen equilibrium decomposition pressure among the plurality of hydrogen absorbing alloys, using the combustion heat from fuel of an internal combustion engine or an external combustion engine of the vehicle as a heat source. Heat of reaction generated by absorption or desorption of hydrogen is utilized for heating or cooling the air in a passenger compartment or a component of the vehicle. The connecting section includes a hydrogen gas storing vessel.

Abstract: A packing band having a superior weld is disclosed. The band can be made of a stretched thermoplastic resin having a flat cross section. The weld is formed by overlapping ends of the band extending in the lengthwise direction thereof. The weld portion of the band includes a plurality of welded sections separated by at least one non-welded section along the lengthwise direction of the band. The welding of the packing band can be accomplished by overlapping parts of the band in a lengthwise direction thereof; melting discontinuous portions of the parts in a pattern along the length of the band parts of a melted portion, an unmelted portion and a melted portion; and then pressing the parts together so that the melted and unmelted portions of the parts contact each other and form a weld.