Tokyo Shibaura Denki Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Tokyo Shibaura Electric Co., Ltd.

Mitsushi Ueno

Tamotsu Shirogami

Noboru Segawa

Yasuji Ogami

Kazuo Saito

Yukihiro Mikogami

Kenji Murata

Hiroshi Chizawa

Tadanori Maoka

Hiroshi 319 Toshiba-Hiyoshi-Ryo-D Chizawa

A polymer electrolyte fuel cells system wherein a reacted gas that has been passed through a cell stack is enabled to be contacted with an unreacted gas to be passed through the cell stack, thereby carrying out a temperature/humidity exchange for the purpose of preventing the drying of a solid polymer electrolyte membrane. The temperature of the unreacted gas is made lower than the temperature of the reacted gas.

Polymer electrolyte fuel cells system

In a fuel cell according to the present invention, a plurality of unit cells each includes an anode and a cathode, each formed of a porous substrate, and an electrolyte matrix layer interposed between the anode and the cathode. A fuel gas channel is formed on one surface of the anode that is located on the side opposite to the electrolyte matrix layer, and an electrolyte-solution permeable portion is formed on the same surface of the anode. The unit cells are stacked in layers, and a plurality of separator elements are interposed between the adjacent unit cells to form a stacked structure. Each of the separator elements has a recess formed on its surface that is located on the side facing the anode. The recess serves to store an electrolyte solution and contain the electrolyte-solution permeable portion. Thus, if an electrolyte solution, with which the electrolyte matrix layer is impregnated, is reduced, the solution stored in the recess permeates the matrix layer, flowing through the permeable portion. As a result, the voltage of the fuel cell is prevented from dropping, thus permitting a prolonged continuous operation of the fuel cell.

Fuel cell

A method of manufacturing a fuel cell assembly, said assembly comprising at least one unit cell, said unit cell comprising at least two planar electrodes, said electrodes being ribbed on one side thereof and having a catalyst layer on the second side thereof, and a matrix impregnated with an electrolyte, comprising the steps of:

Method of manufacturing a fuel cell assembly

A method for manufacturing a fuel cell electrolyte matrix comprises the steps of providing a fuel electrode and oxidizing electrode respectively coated with a catalyst layer on one side, forming a layer of powdery electrolyte-resistive material on the surface of at least one of the catalyst layers, coating a paste layer prepared from acid electrolyte and powdery electrolyte-resistive material on the powder layer or catalyst layer of the fuel electrode and/or the powder layer or catalyst layer of the oxidizing electrode, tightly superposing the fuel electrode and oxidizing electrode on each other with the paste layer and powder layer interposed therebetween, thereby forming an electrolyte matrix between both electrodes.

Fuel cell electrolyte matrix and method for manufacturing the same

A porous gas diffusion electrode for use in an air-metal cell or a hydrogen-air (oxygen) cell comprising an electroconductive porous substrate, which has itself on one surface thereof reaction gas feed channels or is to be used with one surface in contact with reaction gas feed channels during use, and which comprises gas impermeable and electrically insulating seals formed of a tetrafluoroethylene-perfluoroalkyl vinyl ether compolymer provided on the substrate at least at both end portions parallel to said reaction gas feed channels, is capable of positively shielding the gas streams at the end portions parallel to the reaction gas feed channels and maintaining electrical insulation. Such a porous gas diffusion electrode can be prepared by a method comprising applying a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer on the substrate at least at the end portions parallel to the reaction gas feed channels and then subjecting the substrate coated with the copolymer to hot pressure bonding by means of a pressure bonding tool made of a metal previously coated with a fluoride oil to form gas impermeable and electrically insulating seals comprising said copolymer.

Porous gas diffusion electrode and method of producing the same

An electrochemical power generator is disclosed which is composed of a plurality of unit cells stacked with interconnectors interposed therebetween; said unit cells being each composed of an anode consisting of a porous carbon plate having on its one surface a plurality of grooves constituting gas passages and on its other surface an anode catalyst layer; a cathode formed on its one surface with a cathode catalyst layer and applied on its other surface a hydrophobic material powder consisting of fluoropolymer resin; and an electrolyte layer interposed between the anode and the cathode in such a manner that its two surfaces are allowed to come into contact, respectively; said anode catalyst layer and said cathode catalyst layer, the electrolyte layer being prepared by causing an acidic electrolyte to be impregnated into an inorganic compound powder having heat resistance and chemical resistance; the interconnectors being each compressed of a high density carbon plate and having, on each surface coming into contact with the cathode, a plurality of grooves for gas passages, being used as an anode-active material, of a gas consisting mainly of hydrogen and, as a cathode-active material, of an oxidizing gas. First ribs and second ribs wider than said first ribs are formed between adjacent ones of the grooves of the anode substrate, and a catalyst is dispersed in the cathode substrate over a range extending from a boundary between a surface of contact of the cathode substrate with the cathode catalyst layer up to a point located inside the cathode substrate.

Electrochemical power generator

A fuel cell stack has a plurality of stacked unit cells, each consisting of a pair of gas diffusion electrodes with a matrix containing an electrolyte solution interposed between them, with an interconnector having a fuel gas passage on one surface and an oxidizing gas agent passage on the other surface interposed between each pair of adjacent unit cells. One out of every three to five interconnectors is a one-piece-molded product which has at least one cooling pipe embedded in it and which provides an excellent cooling effect. The fuel cell stack stably provides a high output voltage over a long period of operation time.

Fuel cell stack

The invention provides an electrochemical power generator having a structure where a plurality of unit cells are stacked such that each pair of adjacent unit cells sandwich an interconnector therebetween. Each unit cell is formed such that an anode of a porous carbon substrate having an anode catalyst layer on one surface thereof and a cathode of a porous carbon fiber sheet having a cathode catalyst layer on one surface thereof sandwich a matrix layer containing an electrolyte solution of a concentrated acid solution therebetween so as to respectively bring the two surfaces of the matrix layer into tight contact with the anode and cathode catalyst layers. The interconnector is formed of a high density carbon plate. The electrochemical power generator uses as an anode reactant material a gas containing hydrogen as a major component, and uses as a cathode reactant material an oxidizing gas. The electrochemical power generator has excellent mechanical strength and may be efficiently and stably operated without deterioration over a long time. For this purpose, a plurality of grooves which function as a gas passage for the gas containing hydrogen as its major component are formed in the other surface of the anode, the cathode is thinner than the anode and is waterproofed, and a plurality of grooves which function as a gas passage for the oxidizing gas are formed in one surface of the interconnector.

A sealed storage battery comprising a sealed container, an electricity generating means contained in the sealed container and composed of a positive electrode, a negative electrode and an electrolyte, a hydrogen gas oxidation auxiliary electrode disposed within the sealed container, and a resistance means connected to the auxiliary electrode and having an inverse current checking characteristic (or property). In this sealed storage battery, the (critical) point of time of overcharging in charging the sealed storage battery may be detected by monitoring the variation of the voltage between the positive electrode or a separately provided measurement electrode and the auxiliary electrode.

Growing community of inventors

Yokohama, Japan

Mitsushi Ueno