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: A cell according to the present invention is a fuel cell for generating an electric power by supplying one electrode with a fuel and the other electrode with an oxidant. In the fuel cell, a catalyst layer is formed on at least one surface of at least one of the one electrode and the other electrode. The catalyst layer is a layer including catalyst particles alone, a layer including a mixture of the catalyst particles and other particles, or a layer of a porous film carrying at least the catalyst particles, and a molecule including an ion-conducting functional group serving as an electrolyte is chemically bonded to a surface of at least one selected from the group consisting of the catalyst particles, the other particles and the porous film. At least one of the electrodes has a thin film electrolyte, a catalyst and an electron conducting substance, thereby suppressing the elution of the electrolyte from the catalyst layer in an electrode part and the accompanying voltage drop.

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: An electrochemical device for providing an electric energy by converting an electron transfer involved in an oxidation-reduction reaction into an electric energy comprising a positive electrode, a negative electrode and an electrolyte, wherein at least one of the positive and negative electrodes comprises a compound having a structure represented by the general formula (1): 1

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.