Abstract: A fuel cell stack is comprised of a plurality of power generating units which are stacked along the horizontal direction. An oxidant gas inlet port and a fuel gas inlet port are provided in an upper portion of one of the power generating units, and an oxidant gas outlet port and a fuel gas outlet port are provided in the lower portion of the power generating unit. A refrigerant inlet port and a refrigerant outlet port are formed in each of the left and right portions of the power generating unit.

Abstract: A method of controlling humidification of a fuel cell includes the steps of measuring impedance of the fuel cell, and adjusting humidification quantity of the fuel cell based on an imaginary axis value Xi and a real axis value Xr on a complex number plane of the measured impedance after the measurement step. In the measurement step, impedance is measured based on supply of alternating current having one frequency of 10 Hz or less during power generation of the fuel cell.

Abstract: A fuel cell stack is comprised of a plurality of power generating units which are stacked along the horizontal direction. An oxidant gas inlet port and a fuel gas inlet port are provided in an upper portion of one of the power generating units, and an oxidant gas outlet port and a fuel gas outlet port are provided in the lower portion of the power generating unit. A refrigerant inlet port and a refrigerant outlet port are formed in each of the left and right portions of the power generating unit.

Abstract: A method of starting operation of a fuel cell stack includes the steps of performing gas replacement by supplying a fuel gas to a fuel gas flow field from a downstream side of the fuel gas flow field through a fuel gas discharge passage, and supplying an oxygen-containing gas to an oxygen-containing gas flow field from an upstream side of the oxygen-containing gas flow field through an oxygen-containing gas supply passage. After the step of performing gas replacement, normal power generation is carried out by supplying the fuel gas to the fuel gas flow field from an upstream side of the fuel gas flow field through a fuel gas supply passage, and supplying the oxygen-containing gas to the oxygen-containing gas flow field from the upstream side of the oxygen-containing gas flow field through the oxygen-containing gas supply passage.

Abstract: A method of controlling humidification of a fuel cell includes the steps of measuring impedance of the fuel cell, and adjusting humidification quantity of the fuel cell based on an imaginary axis value Xi and a real axis value Xr on a complex number plane of the measured impedance after the measurement step. In the measurement step, impedance is measured based on supply of alternating current having one frequency of 10 Hz or less during power generation of the fuel cell.

Abstract: A fuel cell stack is provided with a pair of refrigerant inlet ports and a pair of refrigerant outlet ports. The refrigerant inlet ports are disposed in the vicinity of an oxidant gas inlet port and a fuel gas inlet port in a manner such that one of the refrigerant inlet ports is disposed on the side of the oxidant gas inlet port and the other refrigerant inlet port is disposed on the side of the fuel gas inlet port. The refrigerant outlet ports are disposed in the vicinity of an oxidant gas outlet port and a fuel gas outlet port in a manner such that one of the refrigerant outlet ports is disposed on the side of the oxidant gas outlet port and the other refrigerant outlet port is disposed on the side of the fuel gas outlet port.

Abstract: A first separator has an outlet side first connection channel connecting a first fuel gas flow field and a fuel gas discharge passage, and a second separator includes an outlet side second connection channel connecting a second fuel gas flow field and the fuel gas discharge passage. The outlet side first connection channel and the outlet side second connection channel include outer passages and outer passages arranged in the same plane formed by facing the first separator and the second separator. The outer passages and the outer passages are formed alternately and independently in the same plane.

Abstract: A fuel cell stack includes power generation devices each including membrane electrode assemblies and corrugated separators. A coolant channel is provided between the power generation devices. A first-end corrugated separator has a first protrusion that protrudes between recesses of the coolant channel in a direction away from one of adjacent membrane electrode assemblies of the membrane electrode assemblies. The first-end corrugated separator is disposed at a first end of each of the power generation devices in a stacking direction. A second-end corrugated separator has a second protrusion that protrudes between recesses of the coolant channel in a direction away from another of the adjacent membrane electrode assemblies. The second-end corrugated separator is disposed at a second end of each of the power generation devices in the stacking direction. The first protrusion and the second protrusion are disposed to be superposed with each other in the stacking direction.

Abstract: A method of starting operation of a fuel cell stack includes the steps of performing gas replacement by supplying a fuel gas to a fuel gas flow field from a downstream side of the fuel gas flow field through a fuel gas discharge passage, and supplying an oxygen-containing gas to an oxygen-containing gas flow field from an upstream side of the oxygen-containing gas flow field through an oxygen-containing gas supply passage. After the step of performing gas replacement, normal power generation is carried out by supplying the fuel gas to the fuel gas flow field from an upstream side of the fuel gas flow field through a fuel gas supply passage, and supplying the oxygen-containing gas to the oxygen-containing gas flow field from the upstream side of the oxygen-containing gas flow field through the oxygen-containing gas supply passage.

Abstract: A fuel cell stack is comprised of a plurality of power generating units which are stacked along the horizontal direction. A corrugated passage groove having a shape corresponding to the shape of the underside surface of a corrugated passage groove of a first fuel gas passage is formed in a surface of a first metal separator. A corrugated passage groove having a shape corresponding to the shape of the underside surface of a corrugated passage groove of a second oxidant gas passage is formed in a surface of a third metal separator. The corrugated passage grooves overlap one another to define a refrigerant passage. An oxidant gas inlet port and a fuel gas inlet port are provided in the upper portion of the power generating unit, and an oxidant gas outlet port and a fuel gas outlet port are provided in the lower portion of the power generating unit. A refrigerant inlet port and a refrigerant outlet port are formed in each of the left and right portions of the power generating unit.

Abstract: A power generation cell includes a membrane electrode assembly, and first and second separators sandwiching the membrane electrode assembly. The first separator includes an oxygen-containing gas flow field. An inlet buffer area is provided between the oxygen-containing gas flow field and an oxygen-containing gas supply passage, and an outlet buffer area is provided between the oxygen-containing gas flow field and an oxygen-containing gas discharge passage. Plural columnar resistance members are provided within the inlet buffer area and the outlet buffer area. The membrane electrode assembly further includes first and second humidification sections.

Abstract: Anodes are provided on a porous resin film, a polymer electrolyte membrane is provided on the anodes, and cathodes are provided on the polymer electrolyte membrane to form a plurality of membrane electrode assemblies as power generation units. An electrically conductive member is connected to the cathode of a membrane electrode assembly, and a metal film is electrically connected to the anode of an adjacent membrane electrode assembly. The electrically conductive member has an expansion connected to the metal film. The cathode of the membrane electrode assembly and the anode of the adjacent membrane electrode assembly are electrically connected by the electrically conductive member and the metal film.

Abstract: In a polymer electrolyte fuel cell in which a cathode diffusion layer, a cathode electrode catalyst layer, a polymer electrolyte membrane, an anode electrode catalyst layer, and an anode diffusion layer are laminated in this order, electron conductivity of the cathode electrode catalyst layer at a portion on the side of the cathode diffusion layer is higher than at a portion on the side of the polymer electrolyte membrane and electron conductivity of the cathode electrode catalyst layer at the portion on the side of the polymer electrolyte membrane is lower than at the portion on the side of the cathode diffusion layer, and furthermore, electron conductivity of the anode electrode catalyst layer at a portion on the side of the anode diffusion layer is higher than at a portion on the side of the polymer electrolyte membrane and electron conductivity of the anode electrode catalyst layer at the portion on the side of the polymer electrolyte membrane is lower than at the portion on the side of the anode diffusio

Abstract: A first separator has an outlet side first connection channel connecting a first fuel gas flow field and a fuel gas discharge passage, and a second separator includes an outlet side second connection channel connecting a second fuel gas flow field and the fuel gas discharge passage. The outlet side first connection channel and the outlet side second connection channel include outer passages and outer passages arranged in the same plane formed by facing the first separator and the second separator. The outer passages and the outer passages are formed alternately and independently in the same plane.

Abstract: A reference electrode is provided adjacent to an anode of a membrane electrode assembly. The potential difference between the reference electrode and the anode is measured by a control unit. The control unit compares the measured value and a map of the anode potential difference stored in the control unit. When the measured value indicates a relation line which is different from a reference line indicating that the fuel gas is sufficient, it is judged that shortage of the fuel gas occurs.

Abstract: A power generation cell includes a membrane electrode assembly, and first and second separators sandwiching the membrane electrode assembly. The first separator includes an oxygen-containing gas flow field. An inlet buffer area is provided between the oxygen-containing gas flow field and an oxygen-containing gas supply passage, and an outlet buffer area is provided between the oxygen-containing gas flow field and an oxygen-containing gas discharge passage. Plural columnar resistance members are provided within the inlet buffer area and the outlet buffer area. The membrane electrode assembly further includes first and second humidification sections.

Abstract: An electrode for a solid polymer fuel cell includes a gas diffusion layer, an electrode catalyst layer disposed between a solid polymer membrane of the fuel cell and the gas diffusion layer, and a water-holding layer disposed between the gas diffusion layer and the electrode catalyst layer. Under high-relative humidity conditions of reaction gases, flooding can be prevented because the electrode catalyst layer is made porous, while under low-relative humidity conditions of reaction gases, sufficient water contents can be stably provided thanks to the water-holding layer so that proton conductivity of the solid polymer membrane can be maintained appropriately. Consequently, high-performance and high-durability electrode and membrane electrode assembly for a solid polymer fuel cell can be provided such that the performance and the durability thereof are not affected by change in relative humidity in reactant gases supplied to the solid polymer fuel cell.

Abstract: In an electrode for polymer electrolyte fuel cells comprising electron conducting particles carrying platinum and an ion conducting polymer, platinum particles formed by a microemulsion method are added in a range of from 5 to 20% of the total amount of platinum in the electrode. A manufacturing method therefor is also provided.

Abstract: A solid polymer electrolyte fuel cell has a fuel electrode and an oxidant electrode, which face each other via a solid polymer electrolyte membrane. A metallic complex is added to the fuel electrode of the solid polymer electrolyte fuel cell. Since this metallic complex adsorbs oxygen as the oxygen partial pressure at the fuel electrode increases and desorbs oxygen as the oxygen partial pressure decreases, oxygen produced when a reverse voltage is generated can be removed efficiently. It may be possible to prevent the deterioration of or damage to a catalyst material of the fuel cell and the electrolyte membrane.

Abstract: A reference electrode is provided adjacent to an anode of a membrane electrode assembly. The potential difference between the reference electrode and the anode is measured by a control unit. The control unit compares the measured value and a map of the anode potential difference stored in the control unit. When the measured value indicates a relation line which is different from a reference line indicating that the fuel gas is sufficient, it is judged that shortage of the fuel gas occurs.