Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Other

Toyota Jidosha Kabushiki Kaisha

The Penn State Research Foundation

Panasonic Ev Energy Co., Ltd.

Masahiro Takada

Toshihiko Ichinose

Katsumi Kozu

Satoshi Shibutani

Hideyuki Ueda

Hirotaka Ishihara

Toshiaki Nakanishi

Akira Ishida

Takashi Akiyama

So Kuranaka

Takeshi Shimamoto

Kazushige Narazaki

Kunio Kanamaru

Shigeru Tsuzuki

Kozo Murakami

Osamu Ito

Naohisa Morimoto

Kunihiro Fujii

Satoshi Matsuo

Kazuhiko Tamesue

Takafumi Koga

Junko Shimamoto, Legal Representative

Noboru Nomura

Yukihiro Okada

Takeshi Yamaguchi

Yoshiaki Kikuchi

Osamu Kawasaki

Kazunori Nishimura

Chao-Yang Wang

Yoshiyuki Nakamura

Kiwamu Inui

Kazuo Tojima

Yusai Murakami

Norito Yamabe

Ichiro Maki

Kazuo Ikeda

Yuji Torii

Teruyoshi Egoshi

Koji Otsubo

A clean power supply unit with a high fuel utilization rate using a fuel cell is provided. The power supply unit of the present invention comprises a fuel cell using methanol as fuel; a secondary battery for supplying power to a load; a fuel cell control part for controlling the amount of fuel and/or air supplied to the above-mentioned fuel cell; and a power converter for converting the power output from the above-mentioned fuel cell to a predetermined voltage or current, supplying power to the load and/or the above-mentioned secondary battery and controlling the supplied power so as to fall within a predetermined range including the value at which the amount of methanol discharged from the above-mentioned fuel cell becomes minimized.

Power supply unit

A method for activating a direct oxidation fuel cell including an anode, a cathode, and a proton-conductive electrolyte membrane interposed between the anode and the cathode is provided. The anode and the cathode each have a catalyst layer on a face in contact with the proton-conductive electrolyte membrane. This method activates the fuel cell by passing a current through the fuel cell from an external power source, with the positive electrode and the negative electrode of the external power source connected to the anode and the cathode of the fuel cell, respectively, while supplying an organic fuel and an inert gas to the anode and the cathode, respectively.

Method for activating fuel cell

A fuel cell system includes: a fuel cell stack including a plurality of fuel cells connected in series; a fuel supply portion supplying a fuel to each fuel cell; a current regulation portion regulating an electric current flowing from the fuel cell stack in such a way that an output voltage of the fuel cell stack is a predetermined set voltage; a voltage detection portion detecting an output voltage of each fuel cell; a fuel-supply control portion regulating a fuel supply to each fuel cell by the fuel supply portion in such a way that the difference decreases between an output voltage of each fuel cell detected by the voltage detection portion; a fuel-stoichiometric ratio detection portion detecting a fuel stoichiometric ratio of the fuel cell stack; and a fuel-stoichiometric ratio control portion regulating the set voltage in such a way that a fuel stoichiometric ratio detected by the fuel-stoichiometric ratio detection portion is a target fuel stoichiometric ratio set in advance.

Fuel cell with fuel-stoichiometric ratio control portion

A method for operating a direct methanol fuel cell is provided. The fuel cell includes a fuel cell main body having a fuel electrode and an air electrode disposed in opposing positions on either side of an electrolyte film. In this method, an aqueous methanol solution is supplied directly to the fuel electrode. A quantity of the aqueous methanol solution supplied is controlled in accordance with an electric current value drawn from the fuel cell main body so as to minimize a quantity of unused methanol within a discharge fluid discharged from the fuel electrode.

Method for operating fuel cell and fuel cell system

A direct oxidation fuel cell of this invention has at least one unit cell including: a membrane-electrode assembly comprising an electrolyte membrane sandwiched between an anode and a cathode, each of the anode and the cathode including a catalyst layer and a diffusion layer; an anode-side separator with a fuel flow channel for supplying a fuel to the anode; and a cathode-side separator with an oxidant flow channel for supplying an oxidant containing oxygen gas to the cathode. The fuel flow channel and the oxidant flow channel are so structured that the concentration of the oxygen gas in the oxidant flow channel is higher at a part opposing an upstream part of the fuel flow channel than at a part opposing a downstream part of the fuel flow channel.

Direct oxidation fuel cell

In a pre-replacement process, a replacement battery module is provided with a memory effect before being dispatched, by performing at least one of the process of performing a cyclic charge/discharge operation on the replacement battery module while limiting the width of SOC change to an intermediate range, and the process of setting an initial SOC and then letting the replacement battery module stand for a predetermined time in an environment of temperature above normal temperature. This pre-replacement process substantially eliminates the difference between the voltage characteristic of the replacement battery module yet to be used and the voltage characteristic of a battery module having a history of use, thereby achieving a uniform voltage characteristic of a battery pack as a whole.

Secondary cell replacing method

A power supply device, comprising first and second lead terminals for connection with a load, a fuel cell, an energy storage element connected between the first and second lead terminals, a synchronous-rectification switching power-source portion for converting the output voltage of the fuel cell to the output voltage of the energy storage element and outputting it to the first and second lead terminals, and a current-detecting portion for detecting the output current of the fuel cell, the switching power-source portion further comprising a first switching element connected to the energy storage element in series, a second switching element connected to the energy storage element in parallel, and a simultaneous-turn-off controller for turning off the first and second switching elements simultaneously when the output current detected by the current-detecting portion is not larger than a preset current threshold.

Power supply device

A method for operating a fuel cell system including a fuel cell stack composed of a plurality of cells connected in series. The method includes the steps of: (a) supplying a fuel and an oxidant to anodes and cathodes of the cells, respectively, depending on a load to generate power at a constant voltage under constant voltage control; (b) temporarily suspending the supply of the oxidant with the fuel being supplied; and (c) lowering the constant voltage to a predetermined voltage simultaneously with or immediately before the suspension of the supply of the oxidant. According to this operation method, when the supply of the oxidant is suspended, a platinum catalyst in the cathodes can be reduced and reactivated in all the cells.

Method for operating fuel cell system

A direct oxidation fuel cell (DOFC) system, comprises at least one fuel cell assembly including a cathode and an anode with an electrolyte positioned therebetween; a source of liquid fuel in fluid communication with an inlet of the anode; an oxidant supply in fluid communication with an inlet of the cathode; a liquid/gas (L/G) separator in fluid communication with outlets of the anode and cathode for: (1) receiving unreacted fuel and liquid and gaseous products, and (2) supplying a solution of fuel and liquid product to the anode inlet; and a control system for measuring the amount of liquid product and controlling oxidant stoichiometry of the system operation in response to the measured amount of liquid product. Alternatively, the control system controls the concentration of the liquid fuel in the solution supplied to the anode inlet, based upon the system operating temperature or output power.

Direct oxidation fuel cell systems with regulated fuel concentration and oxidant flow

A fuel cell system includes a fuel cell including at least one unit cell having an anode, an anode-side flow channel for supplying a fuel to the anode, a cathode, and a cathode-side flow channel for supplying an oxidant to the cathode. The fuel cell system further includes a gas-liquid separator for catalytically purifying the effluent from the anode and the effluent from the cathode to collect liquid. The gas-liquid separator is connected to an anode-side discharge path for the effluent and a cathode-side discharge path for the effluent, which are in fluid communication with a fuel outlet of the anode-side flow channel and an oxidant outlet of the cathode-side flow channel, respectively.

Fuel cell system

A power supply apparatus is provided which includes: a fuel cell; a power storage device which stores electric power; a connection terminal for connecting a load; a charge-used voltage converter which converts the output voltage of the fuel cell into a charging voltage for charging the power storage device and charges the power storage device; and an output-used voltage converter which converts the output voltage of the power storage device into a predetermined set output voltage and outputs it to the connection terminal.

Power supply apparatus

A power supply is provided, which is capable of stabilizing a generated output of the fuel cell using neither a voltage nor a current outputted from the fuel cell as a negative feedback signal. The power supply includes a fuel cell, a DC-DC converterthat adjusts a voltage outputted from the fuel cellaccording to a PWM signal and then outputs the voltage to a load device, a switching controllerthat generates the PWM signal and outputs this signal to the DC-DC converter, a voltmeterthat measures a voltage Vout outputted from the DC-DC converter, and a rechargeable batteryconnected to the load devicein parallel. The DC-DC convertercalculates a duty ratio of the PWM signal by performing a specific computation using the voltage Vout and a target fuel cell voltage Vt.

Power supply

Electronic equipment is provided in which a bi-directional voltage converter is connected between a fuel cell and a secondary battery, and a load apparatus is connected in parallel to the fuel cell. Further, if a plurality of voltage converters are provided, when each output voltage is closer to an output voltage of the secondary battery than an output voltage of the fuel cell, they are classified into a first voltage-converter group, while being closer to the output voltage of the fuel cell than the output voltage of the secondary battery, they are sorted out as a second voltage-converter group. Then, the secondary battery is connected in parallel to the first voltage-converter group and the fuel cell is connected in parallel to the second voltage-converter group.

Electronic equipment, and battery pack and load apparatus used in the same

Growing community of inventors

Shizuoka, Japan

Masahiro Takada