Hitachi, Ltd.

Tsutomu Tsukui

Toshio Shimizu

Motoo Yamaguchi

Ryota Doi

Ryouta Doi

Yoshio Yoshioka

Saburo Yasukawa

Takanori Satoo

Yasuyuki Tsutsumi

Takanori Satou

Shuzou Iwaasa

A liquid fuel cell having a circulation system for a fuel mixture comprising fuel and water, which comprises a first tank containing water or a water-rich fuel mixture comprising water and fuel, a second tank containing fuel or a fuel-rich mixture comprising water and fuel, a first detector for detecting the liquid level of the fuel mixture in the circulation system, a second detector for detecting a fuel concentration of the fuel mixture in the circulation system, or an output from the fuel cell, or a load current of the fuel cell, a valve means for controlling flow of the water or the water-rich mixture in the first tank to the circulation system in accordance with the output from the first detector, and a valve means for controlling flow of the fuel or the fuel-rich mixture in the second tank to the circulation system in accordance with the output from the second detector, can be stably and efficiently operated for a prolonged time in spite of different consumption rates of fuel and water even if the load current or operating temperature of the fuel cell or the temperature or humidity of the atmosphere is changed.

Liquid fuel cell

The disclosure is concerned with a fuel cell battery of an acidic electrolyte type, which comprises means for controlling the flow rate of an oxygen-containing gas, such as air, to be fed to an oxidant electrode of the fuel cell battery in a quantity to completely remove water that is formed on the oxidant electrode by the reaction between fuel and the oxidant from the oxidant electrode. The fuel cell battery prevents lowering of the battery performance due to accumulated water on the oxidant electrode. Also disclosed is means for removing the gas formed at the fuel electrode of the fuel cell from the fuel chamber.

Fuel cell battery using acidic electrolyte

A fuel cell made up of a pile of unit cells, each consisting of a pair of cell element and separator packed in a cell frame, in which there are formed a fuel feed path and oxide product evacuation path in the piling direction. The cell frame is provided between its inner edge offsets and the outer edges of the cell element and separator with inner packings, and further provided near its outer edge on one side with an outer packing. The sealing structure perfectly prevents a fuel leak, and yet allows compactness and easy assembling process.

Fuel cell

In a liquid fuel cell including a plurality of series-connected unit cells each including a fuel electrode and an oxidizer electrode disposed opposite to each other with an electrolyte layer being interposed therebetween, a fuel chamber disposed adjacent to the fuel electrode, and an oxidizer chamber disposed adjacent to the oxidizer electrode, and fuel tanks supplying liquid fuel to the fuel chambers, at least two vertically-spaced passages permitting communication of the fuel tanks with all of the fuel chambers are provided so that one of them serves as a passage for liquid fuel while the other serves as a passage for gas produced at the fuel electrodes, the liquid fuel in an amount smaller than the tank volume is charged in each of the fuel tanks to leave a non-charged space, and gas vent ports provided with gas-liquid separating means are disposed midway of the passages and/or on the tank wall portions corresponding to the non-charged spaces defined in the fuel tanks. The liquid fuel cell can satisfactorily generate power at whatever attitude, and gas produced at the fuel electrodes can be vented to the exterior of the cell without leakage of liquid fuel.

Disclosed is a fuel cell using as an electrolyte an organic, high-molecular weight electrolyte. The fuel cell of the present invention can prevent the leakage of an electrolyte from an electrolyte chamber so that an electrical short-circuit between an anode and a cathode can be avoided. Moreover, use of the disclosed electrolytes permits the fuel to be fed to the fuel chamber by itself or in admixture with water, but without being mixed with electrolyte.

Growing community of inventors

Hitachi, Japan

Tsutomu Tsukui