Abstract: A fuel cell includes a catalysis layer constituting a fuel supply side electrode. The catalysis layer includes a catalyst, an electrically conductive substance, a hydrogen ion-conductive electrolytic substance, and a carbon monoxide oxidizer. As the carbon monoxide oxidizer, for example, particles of a transition metal oxide, chloride, or hydride are used. Alternatively, a metal complex containing water as a ligand can also be used as the carbon monoxide oxidizer.

Abstract: A clean power supply unit with a high fuel utilization rate using a fuel cell is provided. The power supply unit of the present invention comprises a fuel cell using methanol as fuel; a secondary battery for supplying power to a load; a fuel cell control part for controlling the amount of fuel and/or air supplied to the above-mentioned fuel cell; and a power converter for converting the power output from the above-mentioned fuel cell to a predetermined voltage or current, supplying power to the load and/or the above-mentioned secondary battery and controlling the supplied power so as to fall within a predetermined range including the value at which the amount of methanol discharged from the above-mentioned fuel cell becomes minimized.

Abstract: A method for operating a direct methanol fuel cell is provided. The fuel cell includes a fuel cell main body having a fuel electrode and an air electrode disposed in opposing positions on either side of an electrolyte film. In this method, an aqueous methanol solution is supplied directly to the fuel electrode. A quantity of the aqueous methanol solution supplied is controlled in accordance with an electric current value drawn from the fuel cell main body so as to minimize a quantity of unused methanol within a discharge fluid discharged from the fuel electrode.

Abstract: A fuel cell system includes: a dilute tank that stores an aqueous solution of liquid fuel and supplies the solution to the anode of a fuel cell; a fuel tank connected to the dilute tank via a first controlling section; a water tank connected to the dilute tank via a second controlling section; and controlling means including a current detector which measures the amount of the fuel consumed by the fuel cell from the amount of power generation. The controlling means controls the first controlling section based on the measured amount of fuel consumption and further includes correcting means for measuring a component of a gas discharged from the cathode, calculating the amount of the fuel which has crossed over from the anode to the cathode based on the measured component, and correcting the measured amount of fuel consumption based on the calculated amount of fuel crossover.

Abstract: In a fuel cell system, leakage of a fuel and a by-product produced in oxidizing a fuel, and leakage thereof out of a fuel cell by evaporation are prevented. For this purpose, in a fuel cell system comprising an electrogenerating portion having a fuel electrode, an oxidant electrode and an electrolyte sandwiched between the fuel electrode and the oxidant electrode; a fuel accommodating container accommodating a fuel to be supplied to the fuel electrode; a fuel supplying portion supplying a fuel from the fuel accommodating container to the electrogenerating portion; and a fuel discharging portion connected to the fuel electrode, the fuel accommodating container, the fuel supplying portion, the fuel electrode and the fuel discharging portion are air-tightly connected.

Abstract: An MEA is made by: preparing a mixture of a polymer electrolyte and a catalyst; forming, on a transfer sheet, a thin film of the catalyst mixture; transferring the thin film onto one surface of a proton conductive electrolyte membrane for forming a catalyst thin film layer thereon; and repeating the transferring step for forming plural catalyst thin film layers, wherein the transferring steps causes the plural catalyst thin film layers to have a density gradient of sequentially decreasing from its proton conductive electrolyte membrane side to the other side, and wherein the catalyst layer has therein a substantially constant weight ratio of the polymer electrolyte to the catalyst.

Abstract: A power supply system is provided having a fuel cell and a power storage source comprising at least one of a secondary battery and a capacitor, the power supply system being secured to or mounted, in use thereof, on an electronic equipment, wherein: the fuel cell has a maximum output power which is higher than the average power consumption of and lower than the maximum power consumption of the electronic equipment; and the power storage source can output at least a power corresponding to the maximum power consumption of the electronic equipment. The power supply system can start the operation of electronic equipment having a high load even at the time of starting such operation, irrespective of the ambient temperature; can operate the electronic equipment for a long time by simply refilling the fuel supply; and can be low in cost, small in size and high in reliability and output energy density.

Abstract: It is difficult to realize a small fuel cell capable of being installed in mobile device by merely downsizing a conventional fuel cell without changing the configuration. The present invention provides a small fuel cell employing a polymer electrolyte thin film, by using a semiconductor process. A polymer electrolyte thin film fuel cell in accordance with the present invention comprises: a substrate having a plurality of openings; an electrolyte membrane-electrode assembly formed on the substrate so as to cover each of the openings, the assembly comprising a first catalyst electrode layer, a hydrogen ion conductive polymer electrolyte membrane and a second catalyst electrode layer which are formed successively; and fuel and oxidant supply means for supplying a fuel or an oxidant gas to the first catalyst electrode layer through the openings, and an oxidant gas or a fuel to the second catalyst electrode layer.

Abstract: In a fuel cell system, leakage of a fuel and a by-product produced in oxidizing a fuel, and leakage thereof out of a fuel cell by evaporation are prevented. For this purpose, in a fuel cell system comprising an electrogenerating portion having a fuel electrode, an oxidant electrode and an electrolyte sandwiched between the fuel electrode and the oxidant electrode; a fuel accommodating container accommodating a fuel to be supplied to the fuel electrode; a fuel supplying portion supplying a fuel from the fuel accommodating container to the electrogenerating portion; and a fuel discharging portion connected to the fuel electrode, the fuel accommodating container, the fuel supplying portion, the fuel electrode and the fuel discharging portion are air-tightly connected.

Abstract: The present invention relates to a method of manufacturing a compound semiconductor thin film by the thermal decomposition of a metal organic compound and a solar cell using the above thin film. An organic solvent solution of the metal organic compound containing at least one metal-sulfur bond is pulverized into fine particles by an ultrasonic vibration method or by a spray injection method and the obtained fine particles or gaseous metal organic compound are thermally decomposed by contacting them on the heated surface of a thin film forming substrate and thus a compound semiconductor metal sulfide thin film is formed on the thin film forming substrate. With this method, a compound semiconductor thin film of large surface area with uniform quality can be manufactured at low manufacturing cost with good reproducibility. These metal sulfide thin films are of high purity, high density and high quality and thus can be used for various photo-electronic devices.

Abstract: This invention relates to a manufacturing method of a compound semiconductor thin film derived from a metal sulfide produced by thermal decomposition of a sulfur-containing metal organic compound, the compound containing at least one functional group having at least one metal atom selected from the group consisting of copper, zinc, cadmium, mercury, and lead, and the functional group also containing at least one sulfur atom. Since the obtained metal sulfides are of high-purity and dense, they can be utilized in various photoelectric devices. Particularly, the photoelectric conversion efficiency of a CdS/CdTe system thin film compound semiconductor solar cell can be improved remarkably by employing a layer made of a CdS thin film as a window of the solar cell.