Abstract: A power generation cell includes a resin-framed electrolyte membrane electrode assembly. The cathode of the resin-framed membrane electrode assembly has a larger surface dimension than the anode. An outer peripheral portion of the anode is positioned between a first buffer and a fuel gas flow field. An outer peripheral portion of the cathode is positioned between the resin frame member and the second buffer.

Abstract: A power generation cell includes a resin-framed electrolyte membrane electrode assembly. The cathode of the resin-framed membrane electrode assembly has a larger surface dimension than the anode. An outer peripheral portion of the anode is positioned between a first buffer and a fuel gas flow field. An outer peripheral portion of the cathode is positioned between the resin frame member and the second buffer.

Abstract: A method of selecting a thermoplastic-resin adhesive provided so as to be exposed to a fluid flow path of a power generation cell includes a load application step, an exposing step, a measurement step, and a selecting step. In the load application step, a compressive load is applied to a laminate body in a laminating direction thereof, the laminate body being formed by sandwiching an adhesive between a first resin film and a second resin film. In the exposing step, the laminate body is exposed to an environment heated to a predetermined temperature and humidified to a predetermined humidity. In the measurement step, a flow amount of the adhesive during the exposing step is measured. In the selecting step, the adhesive having the flow amount equal to or less than a predetermined amount is selected as an adhesive used for the power generation cell.

Abstract: An electrically insulating resin frame is provided on an outer peripheral side of a power generation section of a membrane electrode assembly forming a fuel cell of a fuel cell stack. A seal bead protruding toward the resin frame is formed on a metal separator. A metal sheet is provided in a portion of the resin frame overlapped with the seal bead as viewed in the stacking direction.

Abstract: In pore diameter distribution curves of a first stack body formed by stacking a first gas diffusion layer and a first porous layer of an anode, and of a second stack body formed by stacking a second gas diffusion layer and a second porous layer of a cathode, on a region where a pore diameter is smaller than a reference pore diameter at which a pore volume is maximum, both the curves coincide with each other for the most part. On a region where the pore diameter is equal to or larger than the reference pore diameter, the distribution curve of the second stack body lies above that of the first stack body. A pore volume ratio which is a ratio of the total pore volume of the second stack body to the total pore volume of the first stack body is in the range of 1.10 to 1.60.

Abstract: A membrane electrode assembly includes a solid polymer electrolyte membrane sandwiched between a pair of electrodes. Each of the electrodes has an electrode catalyst layer and a gas diffusion layer, the electrode catalyst layer facing the electrolyte membrane. A porous layer having a thickness of 5 to 40 ?m and a seepage pressure of 10 to 60 kPa is interposed between the electrode catalyst layer and the gas diffusion layer. The porous layers preferably have a spring constant of 100 to 1000 GPa/m. The membrane electrode assembly may be devoid of any one of the porous layers.

Abstract: A membrane electrode assembly is prepared by sandwiching an electrolyte membrane between an anode and a cathode. In the anode, a first porous layer is interposed between a first electrode catalyst layer and a first gas diffusion layer. In the cathode, a second porous layer is interposed between a second electrode catalyst layer and a second gas diffusion layer. A first piled body of the first gas diffusion layer and the first porous layer has a percolation pressure higher than that of a second piled body containing the second gas diffusion layer and the second porous layer. The first piled body has a percolation pressure of 25 to 120 kPa, and the second piled body has a percolation pressure of 5 to 25 kPa.

Abstract: A membrane electrode assembly includes a solid polymer electrolyte membrane sandwiched between a pair of electrodes. Each of the electrodes has an electrode catalyst layer and a gas diffusion layer, the electrode catalyst layer facing the electrolyte membrane. A porous layer having a thickness of 5 to 40 ?m and a seepage pressure of 10 to 60 kPa is interposed between the electrode catalyst layer and the gas diffusion layer. The porous layers preferably have a spring constant of 100 to 1000 GPa/m. The membrane electrode assembly may be devoid of any one of the porous layers.

Abstract: In pore diameter distribution curves of a first stack body formed by stacking a first gas diffusion layer and a first porous layer of an anode, and of a second stack body formed by stacking a second gas diffusion layer and a second porous layer of a cathode, on a region where a pore diameter is smaller than a reference pore diameter at which a pore volume is maximum, both the curves coincide with each other for the most part. On a region where the pore diameter is equal to or larger than the reference pore diameter, the distribution curve of the second stack body lies above that of the first stack body. A pore volume ratio which is a ratio of the total pore volume of the second stack body to the total pore volume of the first stack body is in the range of 1.10 to 1.60.

Abstract: A membrane electrode assembly is prepared by sandwiching an electrolyte membrane between an anode and a cathode. In the anode, a first porous layer is interposed between a first electrode catalyst layer and a first gas diffusion layer. In the cathode, a second porous layer is interposed between a second electrode catalyst layer and a second gas diffusion layer. A first piled body of the first gas diffusion layer and the first porous layer has a percolation pressure higher than that of a second piled body containing the second gas diffusion layer and the second porous layer. The first piled body has a percolation pressure of 25 to 120 kPa, and the second piled body has a percolation pressure of 5 to 25 kPa.

Abstract: A membrane electrode assembly includes a solid polymer electrolyte membrane sandwiched between a pair of electrodes. Each of the electrodes has an electrode catalyst layer and a gas diffusion layer, the electrode catalyst layer facing the electrolyte membrane. A porous layer having a thickness of 5 to 40 ?m and a seepage pressure of 10 to 60 kPa is interposed between the electrode catalyst layer and the gas diffusion layer. The porous layers preferably have a spring constant of 100 to 1000 GPa/m. The membrane electrode assembly may be devoid of any one of the porous layers.

Abstract: A diffusion layer structure of a fuel cell includes a diffusion layer and a microporous layer. P1/P2 is in a range of 2 to 15 where “P1” is defined as an actual measurement value of pressure drop caused when air penetrates through the diffusion layer having a penetration area of 1.86 cm2 at a flow rate of 2 L/min and where “P2” is defined as a theoretical value of pressure drop defined by formula (1). P2=thickness×10?7×(1?porosity)2/(mean flow pore size2×porosity3)??formula (1) where “thickness” indicates a thickness (?m) of the diffusion layer, “porosity” indicates a porosity (%) of the diffusion layer, and “mean flow pore size” indicates a mean flow pore size (?m) of the diffusion layer.

Abstract: A membrane electrode assembly including: a solid polymer electrolyte membrane having proton conductivity; a cathode electrode catalyst layer disposed on one side of the solid polymer electrolyte membrane; an anode electrode catalyst layer disposed on the other side of the solid polymer electrolyte membrane; and two gas diffusion layers disposed on a side of the cathode electrode catalyst layer and a side of the anode electrode catalyst layer, respectively; wherein the gas diffusion layer in the anode side is smaller in contact angle to water than the gas diffusion layer in the cathode side. The membrane electrode assembly also includes at least two coating layers different in properties from each other between the gas diffusion layer and the cathode electrode catalyst layer, and at least two coating layers different in properties from each other between the gas diffusion layer and the anode electrode catalyst layer.

Abstract: A membrane electrode assembly that includes a cathode electrode catalyst layer and an anode electrode catalyst layer respectively disposed on one side and the other side of a solid polymer electrolyte membrane, gas diffusion layers disposed respectively on the sides of the electrode catalyst layers; and intermediate layers having pores and disposed respectively between the electrode catalyst layer and the gas diffusion layer and between the electrode catalyst layer and the gas diffusion layer. The volume per unit area and per unit mass of the pores having pore size of 0.1 to 10 ?m in the intermediate layer in the cathode side is larger than that in the intermediate layer in the anode side. The pore volume of the intermediate layer in the cathode side is 1.7 to 4.3 ?l/cm2/mg and that of the intermediate layer in the anode side is 0.5 to 1.4 ?l/cm2/mg.

Abstract: The present invention provides a membrane electrode assembly for use in a solid polymer electrolyte fuel cell which assembly can attain an excellent electric power generation performance both under low-humidity conditions and under high-humidity conditions. The membrane electrode assembly includes: a solid polymer electrolyte membrane 2 having proton conductivity; a cathode electrode catalyst layer 3 disposed on one side of the solid polymer electrolyte membrane 2; an anode electrode catalyst layer 4 disposed on the other side of the solid polymer electrolyte membrane 2; and two gas diffusion layers 5 and 6 disposed on a side of the cathode electrode catalyst layer 3 and a side of the anode electrode catalyst layer 4, respectively, both these sides facing away from the solid polymer electrolyte membrane 2; wherein the gas diffusion layer 6 in the anode side is smaller in contact angle to water than the gas diffusion layer 5 in the cathode side.

Abstract: The present invention provides a membrane electrode assembly for use in a solid polymer electrolyte fuel cell which assembly can ensure the gas diffusivity, the capability of discharging the generated water and the moisture retentivity, and can attain an excellent electric power generation performance in the gas atmosphere under a wide variety of humidity conditions. The membrane electrode assembly comprises: a cathode electrode catalyst layer 3 and an anode electrode catalyst layer 4 respectively disposed on one side and the other side of a solid polymer electrolyte membrane 2; gas diffusion layers 5 and 6 disposed respectively on the sides of the electrode catalyst layers 3 and 4; and intermediate layers 7 and 8 comprising pores and disposed respectively between the electrode catalyst layer 3 and the gas diffusion layer 5 and between the electrode catalyst layer 4 and the gas diffusion layer 6. The volume per unit area and per unit mass (pore volume) of the pores having pore size of 0.

Abstract: A membrane electrode structure for a polymer electrolyte fuel cell capable of offering excellent power generation performance both in high humidity conditions and low humidity conditions. The membrane electrode structure for a polymer electrolyte fuel cell is composed of a solid polymer electrolyte membrane 2 having proton conductivity, a cathode electrode catalyst layer 3, an anode electrode catalyst layer 4 and gas diffusion layers 5, 6. The gas diffusion layers 5, 6 have through holes with a mean diameter of 15 to 45 ?m and a specific surface area of 0.25 to 0.5 m2/g, and have a bulk density of 0.35 to 0.55 g/cm3. An intermediate layer 7 is provided between the cathode electrode catalyst layer 3 and the gas diffusion layer 5, and the intermediate layer 7 has through holes with a diameter of 0.01 to 10 ?m and a volume of 3.8 to 7.0 ?l/cm2. The intermediate layer 7 is made of a water-repellent resin containing conductive particles.