Hitachi, Ltd.

New Energy Development Organization

Hideo Okada

Masato Takeuchi

Sigeru Okabe

Fumito Nakajima

Kohki Tamura

Hiroshi Tobita

Munehiko Tonami

Shinpei Matsuda

Toshiki Kahara

Jinichi Imahashi

Shimpei Matsuda

Yoshio Iwase

Tomoichi Kamo

Seizi Takeuchi

Kenzo Ishii

Hirosi Tobita

Kouichi Mitsugi

Akira Kato

Shigeo Uno

Hiroshi Kawagoshi

Toshikatsu Mori

Kazuo Iwamoto

Youichi Sakuta

Satoshi Kuroe

The present invention provides a molten carbonate type fuel cell comprising two electrodes as anode and cathode, an electrolyte plate and separators in a single unit and a battery of the unit cells stacked. The electrodes comprise a porous plate of an electron-conducting material such as nickel containing particles of ceramics such as magnesium oxide uniformly dispersed therein in an amount of 2 to 29 atomic %, except for the superficial thin portion free of the ceramic particles on the one-side surface of the plate. The electrodes are prepared by mixing a powder of the electro-conducting material with an organic binder under stirring to obtain a slurry or paste, deaerating the slurry or paste to remove entrained air bubbles therefrom, shaping the slurry or paste plate with or without a metal wire net, drying the electrode plate at room temperature and finally firing the plate in a reducing atmosphere.

Fuel cell, electrode for the cell and method of preparation thereof

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

A unit cell is formed by a plurality of sub-unit cells as a result of dividing each of the electrodes and electrolytic plate into a plurality of parts. That is, the electrodes and the electrolytic plate are each divided into two parts by electrolytic plate support portions projected from the surfaces of separators. The support portions are pressed in contact with the end portions of the electrolytic plate so as to support the electrolytic plate and seal the reaction gas, preventing it from leaking. The electrolyte support portions of the separators can be provided with electrolyte supply paths, through which the electrolyte is supplied and impregnated into the electrolytic plate. The electrolyte can be supplied via the apertures provided in the separators, to the electrolyte supply paths.

Fuel cell

A fuel cell provided with an electrolyte retaining plate made of electrical insulating long fibers such as lithium aluminate long fibers which have preferably a length of 100 to 400 .mu.m and a diameter of 1 to 4 .mu.m, are interlocked each other and have vacant spaces for filling an electrolyte can be constructed and operated safely without damaging the electrolyte retaining plate for a long period of time.

Process for producing an electrolyte retaining matrix of electrical

A fuel cell comprising a pair of electrodes and an electrolyte body comprising an electrolyte-retainable material and an electrolyte retained in the electrolyte-retainable material, the electrolyte body being provided between the pair of electrodes, characterized by the electrolyte body being integrated with at least one of the pair of the electrodes. The fuel cell has a good sealing between the electrodes and the electrolyte body.

A molten carbonate fuel cell comprising an anode, a cathode and a porous body impregnated with an electrolyte composition of metal carbonates, said body being sandwiched between both the electrodes and being made of one or more refractory, non-electron conductive, inorganic materials containing lithium titanate in an amount sufficient to stabilize said inorganic materials at a temperature of operation of said fuel cell, and operated by supplying a fuel into a fuel chamber placed in the anode side and an oxidant into an oxidant chamber placed in the cathode side, has improved stability for a long period of time and high fuel cell performance.

A fused carbonate type of fuel cell comprising an electrolytic body retaining an electrolyte therein which is arranged between an anode and a cathode, where electricity is electrochemically generated by feeding fuel gas and an oxidant to a fuel chamber arranged on the anode side and an oxidant chamber arranged on the cathode side, respectively, said fuel cell being characterized in that the electrolytic body comprises an electrolyte, an electrolyte-holding member for holding the electrolyte and an inorganic binder.

Fused carbonate 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

In a molten carbonate fuel cell, an anode or cathode is made of a sintered material containing a nickel oxide and/or cobalt oxide and a rare earth element oxide. This anode or cathode has a high activity and is stable at high temperatures.

Molten carbonate fuel cell

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.

The present invention relates to a method for sintering oxidized titanium powder and an active metallic component containing oxidized molybdenum as a binder for oxidized titanium granules. The active metallic component comprises one or more than one selected from a group consisting of V.sub.2 O.sub.3, Fe.sub.2 O.sub.3, WO.sub.3, Co.sub.2 O.sub.3, NiO, Cr.sub.2 O.sub.3, CeO.sub.2, SnO.sub.2, CuO, MoO.sub.3, Pt, Pd, Rh, Ru, Ir and Re. The method comprising the steps of:

Sintered cataltyic or absorbent metallic product and method for

Hydrocarbon oil containing sulfur compounds, for example, lighter petroleum fraction having a boiling point of not higher than 250.degree. C. is hydrodesulfurized to less than 1 ppm with a hydrogenating gas containing 1 to 40% by volume of oxides of carbon (CO.sub.2 and CO) in the presence of a catalyst comprising 3 to 40% by weight of at least one of molybdenum and tungsten, and 2 to 15% by weight of at least one of nickel and cobalt, the balance being titanium oxide. Product gas from steam reforming can be used as the hydrogenating gas.

Growing community of inventors

Hitachi, Japan

Hideo Okada