860 results about "Polymer electrolyte fuel cells" patented technology

A catalyst layer on a substrate material which contains a proton-conducting polymer (ionomer), electrically conductive carbon particles and fine particles of at least one precious metal. The catalyst layer is obtainable by coating the substrate material with an ink which contains a dispersion of the carbon particles and at least one organic precious metal complex compound in a solution of the ionomer, and drying the coating below a temperature at which the ionomer or the substrate material is thermally damaged, the precious metals in the complex compounds being present with an oxidation number of 0 and the complex compounds being thermally decomposed during drying to form the fine precious metal particles.

A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various thermoplastc polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes. With the thermally resistant polymer, e.g., polybenzimidazole or a mixture of polybenzimidazole and other thermoplastics as binder, the carbon-supported noble metal catalyst is tape-cast onto a hydrophobic supporting substrate. When doped with an acid mixture, electrodes are assembled with an acid doped solid electrolyte membrane by hot-press. The fuel cell can operate at temperatures up to at least 200° C. with hydrogen-rich fuel containing high ratios of carbon monoxide such as 3 vol % carbon monoxide or more, compared to the carbon monoxide tolerance of 10-20 ppm level for Nafion®-based polymer electrolyte fuel cells.

Corrugated flow field plates for use in fuel cells typically comprise a plurality of parallel open-faced fluid flow channels for the fuel cell reactants. Complex flow paths, such as serpentine flow paths, may be created in such corrugated flow field plates by incorporating channel couplings within the plate or by attaching coupling subassemblies to the plate. The plates are particularly suitable for use in solid polymer electrolyte fuel cells.

An electrolyte membrane is prepared from a liquid composition comprising at least one member selected from the group consisting of trivalent cerium, tetravalent cerium, bivalent manganese and trivalent manganese; and a polymer with a cation-exchange group. The liquid composition is preferably one containing water, a carbonate of cerium or manganese, and a polymer with a cation-exchange group, and a cast film thereof is used as an electrolyte membrane to prepare a membrane-electrode assembly. The present invention successfully provides a membrane-electrode assembly for polymer electrolyte fuel cells being capable of generating the electric power in high energy efficiency, having high power generation performance regardless of the dew point of the feed gas, and being capable of stably generating the electric power over a long period of time.

A membrane electrode assembly for a polymer electrolyte fuel cell characterized by using, as solid polyelecrolyte of at least one of a membrane and a catalyst binder, a fluorinated sulfonic acid polymer with a monomer unit represented by the following general formula (3):

(wherein Rf¹ is a bivalent perfluoro-hydrocarbon group having a carbon number of from 4 to 10), wherein said fluorinated sulfonic acid polymer has melt flow rate (MFR) not higher than 100 g/10 min at 270° C. when a —SO₃H group in said polymer is converted to —SO₂F.

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. Each of the anode-side conductive separator plate and the cathode-side conductive separator plate is rectangle in shape and has an oxidant gas manifold aperture for an inlet arranged on one short side thereof, an oxidant gas manifold aperture for an outlet arranged on the other short side thereof, a fuel gas manifold aperture for an inlet and a fuel gas manifold aperture for an outlet arranged on different longitudinal sides thereof, and a cooling water manifold aperture for an inlet and a cooling water manifold aperture for an outlet arranged on the different longitudinal sides thereof. The respective fuel gas manifold apertures are disposed opposite to the cooling water manifold apertures. The oxidant gas manifold apertures, the fuel gas manifold apertures, and the cooling water manifold apertures have openings of different shapes.

A membrane electrode assembly for polymer electrolyte fuel cells comprises a cathode electrode, an anode electrode, and a polymer electrolyte membrane placed between these electrodes, and a catalyst material of Pt—Ru alloy is contained in the anode and the crystal of Pt—Ru alloy is mainly of a face-centered cubic structure.

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.

A polymer electrolyte fuel cell comprising 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 gas flow channels for supplying a fuel gas to the anode, and a cathode-side conductive separator plate having gas flow channels for supplying an oxidant gas to the cathode, wherein the anode-side and cathode-side conductive separator plates have a substantially rectangular part in contact with the anode or cathode in which the length of a longer side is equal to or more than twice the length of a shorter side, and the oxidant gas flow channels have a linear part formed along the longer side of the rectangular part.

To provide a membrane/electrode assembly for polymer electrolyte fuel cells, which is capable of providing high power generation performance even under a low humidity condition and has sufficient mechanical strength and dimensional stability, and which has an excellent durability even in an environment where moistening and drying are repeated, and a polymer electrolyte fuel cell which is capable of providing high power generation performance even under a low humidity condition.

A membrane/electrode assembly 10 is used, which comprises a cathode 20 having a catalyst layer 22, an anode 30 having a catalyst layer 32, and a polymer electrolyte membrane 40 interposed between the catalyst layer 22 of the cathode 20 and the catalyst layer 32 of the anode 30, wherein at least one of the cathode 20 and the anode 30 further has a reinforcing layer 26 comprising a porous sheet-form reinforcing material made of a polymer, and an electrically conductive fiber.

An object of the present invention is to provide a solid polymer electrolyte membrane in which a polyazole-based compound is uniformly mixed with a perfluorocarbonsulfonic acid resin. Thus, the present invention provides a solid polymer electrolyte membrane for solid polymer electrolyte fuel cell, which has high durability, as well as a membrane electrode assembly and a solid polymer electrolyte fuel cell, each containing the same. The inventive solid polymer electrolyte membrane is produced by a method which comprises a polymer electrolyte-containing solution preparation step of dissolving a perfluorocarbonsulfonic acid resin (component A) having an ion-exchange capacity of 0.5 to 3.0 meq/g, a polyazole-based compound (component B) and an alkali metal hydroxide in a protic solvent to prepare a polymer electrolyte-containing solution in which a weight ratio of the component A to component B, (A/B), is from 2.3 to 199 and a total weight of the component A and the component B is from 0.5 to 30% by weight; and a membrane formation step of forming a membrane from the polymer electrolyte-containing solution.

A solid polymer fuel cell which can stably generate electric power for long, because the cell is enabled to uniformly supply a fuel gas to all anodes by means of extended flow passages which are extended from anode-side flow passages and formed on a anode-side plate on the downstream side of the ends of the anodes in the direction of fuel gas flow, a water absorbing means for nearly uniformly performing water absorption, water retention, and drainage on all channels provided at the ends of the extended flow passages, and a selective gas discharging means for discharging a gas more selectively than water on the upstream side of the water absorbing means. In addition, the power generation characteristics and service life of the fuel cell can be improved further, because the cell can maintain a solid polymer film in a moist state as a whole and can efficiently supply the fuel gas to all anodes by a means for distributing the fuel gas to the inlet sections of the anode-side flow passages and a means for distributing water from a water source to the inlet sections of the anode-side flow passages through holes having a prescribed form and leading to the inlet sections of the anode-side flow passages.

To provide a polymer electrolyte membrane having excellent size stability and excellent mechanical strength that can sufficiently prevent the size change due to the swelling condition, the displacement of the polymer electrolyte membrane and the formation of wrinkles during the production of the polymer electrolyte fuel cell, and can prevent damage during the production and operation of the polymer electrolyte fuel cell. In a composite electrolyte membrane including a porous reinforcement layer made of a resin and an electrolyte layer made of a polymer electrolyte and laminated at least one main surface of the reinforcement layer, the direction having a high tensile modulus of elasticity in the reinforcement layer is substantially corresponded with the direction having a high rate of size change in the electrolyte layer.

The invention provides an MEA-gasket assembly (1) comprising: an MEA (5) having a polymer electrolyte membrane (5A), catalyst layers and gas diffusing layers (5C); a plate-like frame (6) which is joined to a portion of the polymer electrolyte membrane (5A) so as to enclose the MEA (5), the portion being located in a peripheral region of the MEA (5) and which has a plurality of fluid manifold holes (12, 13, 14); and an annular gasket (7) formed on both faces of the frame (6), wherein an annular gap formed between the inner peripheral edge of the annular gasket (7) and the outer peripheral edges of the gas diffusing layers (5C) is at least partially closed.

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.

A rubber composition comprising (A) a polyisobutylene polymer having an allyl radical at an end, (B) an optional organpolysiloxane, (C) an organohydrogenpolysiloxane having at least two SiH radicals per molecule, and (D) a platinum group metal catalyst forms a seal member on a periphery of one side of a polymer electrolyte fuel-cell separator. Due to improved acid resistance, weather resistance, creep resistance and gas permeability, the seal member remains effective for a long period of time.

A polymer electrolyte fuel cell consists of plural units, and the unit has an anode side separator, an anode diffusion layer, an anode catalytic layer, polymer electrolyte membrane, a cathode catalytic layer, a cathode diffusion layer, and a cathode side separator. The cathode catalytic layer further includes a catalyst in which platinum or platinum alloy is supported on a carbon supporting body having an average lattice space d002 of [002] surface of 0.338 to 0.355 nm and specific surface area of the supporting body of 80 to 250 m²/g, electrolyte containing ion exchange resin, and vapor grown carbon fiber. Furthermore, a water holding layer containing ion exchange resin, carbon particles, and vapor grown carbon fiber is arranged at an interface of the cathode diffusion layer and the cathode catalytic layer.

A highly corrosion-resistant material and a corrosion-resistant member which are improved in corrosion resistance, adhesion, contact electrical resistance, electrical conductivity, airtightness, etc. and are suitable for use as, e.g., a metallic separator for polymer electrolyte fuel cells (PEFC); and a process for producing them. A thin noble-metal layer is formed on the desired part of the surface of a metallic base and then subjected to compression working. The coated base may further be subjected to anticorrosive treatment with a liquid phase containing a peroxide or ozone or with an active gas atmosphere.