Abstract: A cell voltage measuring device for a fuel cell includes a terminal member to be connected to a separator of the fuel cell, the terminal member including a first end and a second end, and a voltage measuring unit which measures cell voltage of the fuel cell through the terminal member. The first end of the terminal member is fixed to the voltage measuring unit, and the second end of the terminal member makes contact with the separator, and an elastic portion is provided between the first end and the second end of the terminal member. The cell voltage measuring device may further includes a holder member which is capable of maintaining a state in which the second end of the terminal member is separated from each other, and the holder member is movably attached in a stacking direction of the separator with respect to the voltage measuring unit.

Abstract: A cell voltage detector for fuel cell comprising terminals adapted to be brought into abutment with output terminals of separators for a stack, a voltage detecting unit for detecting the cell voltage of the stack through the terminals, a terminal holder for holding one end of the respective terminals and permitting the abutment of the terminals with the output terminals of the separators via a terminal opening opened in a fuel cell cover for encompassing the stack, the terminal holder having a leg portion adapted to be brought into abutment with the periphery of the terminal opening and a terminal cover retained onto the fuel cell cover, so that the terminal cover is brought into abutment with a head portion of the terminal holder on an inner surface thereof and covers the periphery of the terminal opening.

Abstract: First gas flow passage grooves which communicate with an oxygen-containing gas inlet, and second gas flow passage grooves into which the first gas flow passage grooves are merged and which communicate with an oxygen-containing gas outlet are provided on a surface of a first separator. First communication passages and second communication passages for enabling the air to flow therethrough are provided at first and second bent sections of the first gas flow passage grooves and the second gas flow passage grooves. Accordingly, when the air flowing in the surface of the separator is bent over, then the flow rate of the air is not partially lowered, and it is possible to reliably remove produced water.

Abstract: In order to improve detecting accuracy in a gas leak detection for a fuel cell, in a gas leak detection method for a fuel cell having a solid polymer electrolyte membrane sandwitched by an anode and a cathode, an output voltage is measured in an activated over-potential region in a state in which the pressure of fuel gas which is supplied to the anode is maintained higher than the pressure of gas which is supplied to the cathode, and a gas leak is determined to exist when the output voltage is lower than a predetermined pressure value.

Abstract: A fuel cell which can self-heat in a short time, in which no reaction gas is necessary for combustion, thereby improving the starting performance at low temperatures. The fuel cell comprises a cell structure in which an anode and a cathode are provided on either side of a solid polymer electrolyte membrane. This cell structure has a power generation plane and at least a part of the generation plane is defined as a local generation area so as to locally generate power. The fuel cell may include a pair of separators between which the cell structure is placed, and a reaction gas passage may be formed between the cell structure and each separator. One of a system for supplying a reaction gas to only a part of the reaction gas passage, and a system for supplying a reaction gas to the entire reaction gas passage is switchably selected.

Abstract: A first separator has its surface which is designed to have a rectangular configuration. A fuel gas flow passage for making communication between a fuel gas inlet and a fuel gas outlet is provided on the surface. The fuel gas flow passage is designed to have a meandering configuration so that it extends in a long side direction and it turns back on a short side to allow a fuel gas to flow in the direction of the gravity. Accordingly, it is possible to effectively shorten a size in the height direction, and it is possible to obtain desired power generation performance with a simple structure.

Abstract: Disclosed is a fuel cell stack comprising fuel cell units and first and second separators which are alternately stacked with each other. Wedge members are integrally inserted, over the plurality of fuel cell units, into communication holes of a fuel gas supply passage, an oxygen-containing gas supply passage, and a cooling water supply passage, as well as a fuel gas discharge passage, an oxygen-containing gas discharge passage, and a cooling water discharge passage. A fluid is uniformly delivered to each of the fuel cell units by the aid of the wedge members. Accordingly, the fluid of any one of a fuel gas, an oxygen-containing gas, and a cooling medium is uniformly delivered to each of the fuel cell units. Further, it is possible to simplify the arrangement of the fuel cell stack.

Abstract: Each of cooling medium flow passages provided for a first separator includes single main flow passage grooves communicating with a cooling medium inlet and a cooling medium outlet respectively, and branched flow passage grooves formed and branched between the main flow passage grooves. Accordingly, it is possible to greatly decrease the flow passage length. Therefore, it is possible to effectively avoid the occurrence of flow passage pressure loss in the superficial direction of the first separator, and it is possible to improve the system efficiency of the power generation.

Abstract: The fuel cell of the present invention comprises: a membrane electrode assembly including an electrolyte membrane held between an anode electrode and a cathode electrode; an anode side separator and a cathode side separator clamping the membrane electrode assembly; an oxidant gas channel provided on the cathode side separator, the oxidant gas channel starting from an oxidant gas channel inlet and reaching an oxidant gas channel outlet, the oxidant gas channel having a U-shape comprising a first route, a turning portion, and a second returning route; and a fuel gas channel provided on the anode side separator, the fuel gas channel starting from a fuel gas channel inlet and reaching a fuel gas channel outlet, the fuel gas channel having a U-shape comprising a first route, a turning portion, and a second returning route.

Abstract: A fuel cell is provided wherein the production of a separator is easy and a reactant gas channel thereof can be easily arranged. The fuel cell is constituted by clamping an electrolyte membrane electrode assembly provided with an anode and a cathode at opposite positions on both sides of an electrolyte membrane, by a pair of separators via a sealing member. A part of a reactant gas channel formed between the electrolyte membrane electrode assembly and the cathode side separator is formed seamlessly by extended portions of the sealing member.

Abstract: Disclosed is a fuel cell stack comprising a fuel cell unit and separators which are stacked with each other. The separator is provided with a cooling medium supply port corresponding to a central portion of an electrode power-generating section and a cooling medium discharge port corresponding to an outer circumferential portion of the electrode power-generating section. The cooling medium supply port communicates with the cooling medium discharge port via a cooling medium flow passage having a spiral configuration. Accordingly, the entire fuel cell unit can be uniformly cooled, and the power-generating function can be effectively improved.

Abstract: First gas flow passage grooves communicating with a fuel gas inlet and second gas flow passage grooves communicating with a fuel gas outlet are provided on a surface of a first separator. First and second united sections are provided at merged portions of the first gas flow passage grooves and the second gas flow passage grooves. Accordingly, the number of gas flow passage grooves is throttled from the side of the fuel gas inlet to the side of the fuel gas outlet. The turbulence is allowed to occur at the throttled portion to make it possible to improve the gas diffusion performance.

Abstract: A fuel cell stack comprises first and second separators for holding a fuel cell unit therebetween. The first separator has a fuel gas flow passage and the second separator has an oxygen-containing gas flow passage. The gas flow passages are formed by grooves with the number of grooves decreasing from the inlet to the outlet. In one embodiment, the gas flow passage comprises twelve individual first gas flow passage grooves which communicate with an inlet hole on a gas inlet side, six individual second gas flow passage grooves which communicate with the first gas flow passage grooves, and three individual third gas flow passage grooves which communicate with the second gas flow passage grooves. The third gas flow passage grooves communicate with an outlet hole on a gas outlet side.