Hitachi, Ltd.

Hitachi Chemical Company, Ltd.

New Energy Development Organization

Toshiki Kahara

Kohki Tamura

Jinichi Imahashi

Seizi Takeuchi

Akio Honji

Kenzo Ishii

Masato Takeuchi

Keizou Ohtsuka

Shimpei Matsuda

Hideo Okada

Noboru Ebato

Tatsuo Horiba

Shinpei Matsuda

Shigeaki Namba

Toshikatsu Mori

Sigeru Okabe

Yasutaka Komatsu

Tsutomu Takahashi

Tomoichi Kamo

Fumito Nakajima

Shin Takahashi

Osamu Yokomizo

Tsutomu Okusawa

Osamu Asai

Nobuhiro Seiki

Fumio Sato

Hiroaki Suzuki

Kazuo Iwamoto

Tadashi Yoshida

Hiroshi Tobita

Tomio Yoshida

Yoshio Iwase

Kunko Kitami

Takaaki Mizukami

Kouichi Mitsugi

Hirosi Tobita

Shoji Takahashi

Tatuo Horiba

Noboru Ebata

Toshihiro Saitoh

Kouichi Chino

Shuhei Yamaguchi

Sei Takashima

Tatsuo Sakamoto

During a time zone where a power demand is smaller than an average value of the entire power demands of homes, an excess portion obtained by subtracting a power demand from a base power portion supplied by PEFC () is charged in a capacitor () and a lead storage battery () in advance; and during a time zone where a power demand is larger than the average value, a peak power portion exceeding this average value is discharged from the capacitor () and the lead storage battery (); thereby enabling the system to sufficiently meet daily home-use demand with requisite minimum equipment while effectively using surplus power. Thus, energy efficiency can be enhanced without wasting energy, and also cost efficiency can be improved.

Home-use fuel cell system

A faulty chemical reactor in a chemical plant is removed, heat exchange is conducted between the faulty chemical reactor and a new chemical reactor with which the faulty chemical reactor is to be replaced, and then the new chemical reactor is installed at the position from which the faulty chemical reactor was previously removed.

Chemical reactor replacement method

Molten carbonate type or phosphoric acid type fuel cells and a method for supplementing these fuel cells with an electrolyte are disclosed. A fuel cell having an extended life is provided by scattering a plurality of sealed supplementary electrolyte containers made of a material which is soluble in the electrolyte at elevated temperatures, and supplying the supplementary electrolyte from the dissolved containers to the fuel cell while the cell is working.

Fuel cell and supplementary electrolyte container and method for

There is disclosed a chemical reaction installation in which a number of chemical reaction vessels are arranged efficiently so as to decrease an installation area while keeping a good maintainability. A processing system is provided at the inside, and a multi-story construction is provided, and access for maintenance purposes can be obtained from the side of each floor of the multi-story construction.

Chemical reaction installation

A fuel cell has a plurality of fuel cell sub-stacks each of which has cell bodies, at least one anode header and at least one cathode header and which are stacked to form a fuel cell stack body, and side thermal insulators which are provided on the side of the fuel cell stack body so as to keep the fuel cell sub-stacks warm and which are discrete from each other in the direction of stacking of the fuel cell sub-stacks, each of the plurality of side thermal insulators being independently supported.

Insulated fuel cell

The invention relates to internal-reforming fuel cells. They are each constructed of plural unit cells stacked one over another. Each unit cell is formed of a cathode, an electrolyte plate, an anode and a separator. Each unit cell also includes a generating zone formed by the cathode, anode and electrolyte plate; a reforming zone for reforming fuel gas; a fuel gas flow channel communicating with a fuel gas inlet and a fuel gas outlet and including a divided fuel gas flow channel for the unit cell; and an oxidant gas flow channel communicating with an oxidant gas inlet and an oxidant gas outlet and including a divided oxidant gas flow channel for the unit cell. The reforming zone is arranged in the fuel gas flow channel while the generating zone is arranged in contact with the fuel gas flow channel and the oxidant gas flow channel at a position downstream of the reforming zone while the fuel gas and oxidant gas are maintained separated from each other.

Internal-reforming fuel cells and power stations using the same

The present invention provides a fuel cell which is improved in creep resistance and sintering resistance of anode and in activity of anode and which can maintain high performance over a long time. This fuel cell comprises a laminate comprising an electrolyte holding material having pores for holding an electrolyte, an anode and a cathode which sandwich the electrolyte holding material and a separator provided with grooves for feeding a gas to the anode and cathode characterized in that the anode is a ternary anode which comprises nickel as a main component and additionally cobalt and chromium oxide.

Fuel cell

A molten carbonate fuel cell using molten carbonate as an electrolyte, carbonate ions as electric conductor, and feeding a hydrogen-enriched gas to the anode and a mixture of air and carbon dioxide gas to the cathode has its output fall by degrees with operation. It is surmised that one of the causes of this problem is ascribable to the fact that the molten carbonate electrolyte moves during operation to destroy equilibrium in the boundary between the electrolyte and electrodes. After studies for measures against the problem, the inventor found that the output of a fuel cell which has fallen can be improved by shutting off part or all of the raaction gases or reducing their feed for a while, and then restoring. The purpose of the present invention is to offer a high-performance stable-output molten carbonate fuel cell and its operation control method, incorporating the above findings in its operation control system.

Molten carbonate fuel cell, and its operation control method

In a fuel cell comprising a pair of counterposed gas-diffusible electrodes, an electrolyte-retaining, porous matrix provided between and in contact with the electrodes, a fuel chamber for feeding a gaseous fuel to the anode of the pair of the electrodes and an oxidizing agent chamber for feeding a gaseous oxidizing agent to the cathode of the pair of the electrodes, the cell performance is remarkably prevented from lowering by making the electrolyte saturated absorption amount of the cathode smaller than that of the anode, thereby preventing migration of the electrolyte in the electrolyte-retaining matrix.

In a fuel cell comprising an electrolyte-retaining matrix interposed between a pair of gas-diffusion electrodes, the matrix comprises particles or fibers of a substance unreactive with phosphoric acid and having electron-insulating properties and an inorganic binder.

Method of making fuel cell

In operating a fuel cell comprising an oxidizing agent chamber subject to supply of an oxidizing agent gas and a fuel chamber subjected to supply of a fuel gas, sintering of noble metal particles such as platinum black as an electrode catalyst can be prevented from sintering by connecting the fuel cell to an outside auxiliary load circuit and controlling the unit cell voltage to not more than 0.80 V at start or discontinuation to operate the fuel cell or during the operation of the fuel cell when an outside load becomes too low due to fluctuation of the outside load. The fuel cell performance can be improved thereby.

Method for operating fuel cell

A fuel cell comprising a pair of gas diffusion electrodes, an electrolyte retaining matrix disposed between said gas diffusion electrodes, and a phosphoric acid electrolyte disposed within said matrix, characterized by using as matrix that comprising one or more metal oxides having electronic insulation and insolubility in phosphoric acid and a binder is excellent in phosphoric acid retaining ability and can be used for a long period of time without degradation of the performance of fuel cell.

A fuel cell electrode being substantially free from cracks on the surface of catalyst layer on the electrode and having a good electrode performance under the atmospheric pressure or under pressure when assembled into a fuel cell, which comprises a gas-diffusing electroconductive substrate with continued pores and a water-repellent catalyst layer comprising electroconductive submicron particles having a catalyst, electroconductive materials each having a volume 10.sup.3 -10.sup.10 as large as the volume of the largest particle of the submicron particles and, if necessary, having a catalyst, and a water-repellent polymer as a binder, the electroconductive submicron particles and the electroconductive materials being provided in a mixing ratio by volume of the former to the latter of 95-50 to 5-50.

Fuel cell electrode

Fuel cell with improved and stabilized electrode performance having at least one gas diffusion electrode, where the gas diffusion electrode comprises an electronconductive, gas-permeable substrate and an electrode catalyst uniformly distributed on the substrate, the electrode catalyst comprising colonies each consisting of not more than 20 primary particles of noble metal each having a size of 10-30 A and being uniformly distributed and deposited on carrier powder.

Growing community of inventors

Ibaraki, Japan

Toshiki Kahara