Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Other

Asahi Glass Company, Limited

Shinya Kosako

Masao Yamamoto

Kenji Nakao

Tsuyoshi Uemura

Makoto Uchida

Hirofumi Kubota

Yasushi Sugawara

Noriko Naito

Junji Morita

Akihiko Yoshida

Eiichi Yasumoto

Osamu Sakai

Yoshihiro Hori

Yoichiro Tsuji

Kazuhito Hatoh

Seiji Nishiyama

Kazuo Inoue

Masataka Ozeki

Akinari Nakamura

Yasuo Takebe

Soichi Shibata

Hideaki Mochizuki

Takayuki Urata

Yoshikazu Tanaka

Takahiro Umeda

Hisako Kurai

Masaki Yamauchi

Hiroki Kusakabe

Teruhisa Kanbara

Hisaaki Gyoten

Shigehiro Sato

Masato Hosaka

Yoshio Iwai

Hiroaki Mizuno

Miho Gemba

Takeshi Yonamine

Yoshikazu Ip Development Center Tanaka

Yoshikazu c/o Matsushita Electric Industrial Co Ltd Tanaka

A fuel cell system includes a fuel cell; a fuel gas supplying unit supplying the fuel gas into the fuel cell on the anode side thereof; an oxidizing agent gas supplying unit supplying the oxidizing agent gas into the fuel cell on the cathode side thereof; a raw material gas supplying unit supplying the raw material gas into the fuel cell; and a controlling unit controlling the supply of the fuel gas, the oxidizing agent gas and the raw material gas. After switching the output of electric power or the fuel cell off, the fuel gas supplying unit suspends the supply of the fuel gas, the oxidizing agent gas supplying unit suspends the supply of the oxidizing agent gas and the raw material gas supplying unit supplies the raw material gas into the fuel cell to purge the fuel cell on the cathode side.

Fuel cell system and method for stopping operation of fuel cell system

Problems of acceleration of drying of electrolyte membrane and local reaction, etc. can be properly coped with to attain the stabilization of performance of fuel cell. There are provided a fuel cellwhich generates electric power from a fuel gas and an oxidizing agent gas, a fuel gas feed pipeand a first switch valveas fuel gas supplying unit which supplies the said fuel gas into the said fuel cell on the anode side thereof, an oxidizing gas supplying pipeand a second cut-off valveas oxidizing agent gas supplying unit which supplies the said oxidizing agent into the said fuel cell on the cathode side thereof, a raw material gas supplying pipeand a third switch valveas raw material gas supplying unit which supplies raw material of the said fuel gas into the fuel cell and a control portionwhich controls the supply of the said fuel gas, the supply of the said oxidizing agent and the supply of the said raw material and the control portioncontrols during the starting of electricity generation of the fuel cellsuch that the said raw material gas supplying unit purges the fuel cellat least on the cathode side thereof with the said raw material gas before the oxidizing agent gas supplying unit and the fuel gas supplying unit supply the fuel gas and the said oxidizing agent gas into the fuel cell, respectively.

Fuel cell system, method of starting fuel cell system

A method of operating a fuel cell capable of suppressing degradation of a fuel cell caused by starting and stopping of the fuel cell, including carrying out a restoring operation by decreasing a voltage of the cathode following termination of the fuel cell.

Method of operating fuel cell system and fuel cell system

In order to obtain an electrolyte membrane-electrode assembly using a thin electrolyte membrane, the present invention provides a production method of an electrolyte membrane-electrode assembly comprising: a step of forming a hydrogen ion-conductive polymer electrolyte membrane on a base material; a treatment step of reducing adhesion force between the base material and the hydrogen ion-conductive polymer electrolyte membrane; a step of separating and removing the base material; and a step of bonding a catalyst layer and a gas diffusion layer onto the hydrogen ion-conductive polymer electrolyte membrane, and, in order to obtain an electrolyte membrane-electrode assembly which has a catalyst without clogging and is excellent in electrode characteristics, the present invention provides a production method of an electrolyte membrane-electrode assembly comprising: a step of bonding a hydrogen ion-conductive polymer electrolyte membrane and a catalyst layer via a coating layer; a step of removing the coating layer; and a step of obtaining an electrolyte membrane-electrode assembly by forming a gas diffusion layer on the catalyst layer.

Method for manufacturing fuel cell electrolyte film-electrode bond

A carbon fiber woven fabric for use as a gas diffusion layer base material in a polymer electrolyte fuel cell has a surface that is smoothed and further optimized to inhibit non-uniform infiltration of a coating for water-repellent-layer formation, to provide an electrolyte membrane-electrode assembly suitable for operation under a high humidification condition. The gas diffusion layer base material may be a carbon fiber woven fabric, wherein a ratio of the area of gap portions where neither warp thread nor weft thread exists: (10/W&#x2212;Y)(10/Z&#x2212;X) to the area of portions where warp thread is crossing weft thread: XY mmis in the range of about 1/1500 to about 1/5, where the carbon fiber woven fabric has a warp density of Z threads/cm, a weft density of W threads/cm, a warp thickness of X mm and a weft thickness of Y mm.

Electrolyte membrane-electrode assembly for fuel cell and operation method of fuel cell using the same

The present invention provides a polymer electrolyte fuel cell having an increased reaction area by forming a gas channel, a proton channel and an electron channel very close to each other inside a catalyst layer. This polymer electrolyte fuel cell includes a hydrogen ion conductive polymer electrolyte membrane; and a pair of electrodes having catalyst layers sandwiching the hydrogen ion conductive polymer electrolyte membrane between them and gas diffusion layers in contact with the catalyst layers, in which the catalyst layer of at least one of the electrodes comprises carbon particles supporting a noble metal catalyst, and the carbon particles include at least two kinds of carbon particles adsorbing a hydrogen ion conductive polymer electrolyte in mutually different dispersed states.

Method for manufacturing polymer electrolyte fuel cell

Polymer electrolyte fuel cell

A fuel cell component includes an electrolyte membrane and insert members disposed within the electrolyte membrane. The insert members are arranged to provide compression resistance of the assembly of the insert members and electrolyte membrane. Creep resistance of the assembly of the insert members and electrolyte membrane is greater than a creep resistance of the electrolyte membrane alone.

Fuel cell and process for the production of same

By using a gas diffusion layer for a fuel cell comprising a fabric comprising a warp thread and a weft thread which are made of carbon fiber, wherein the distance X between adjacent intersections where the warp and weft threads cross each other and the thickness Y of the fabric satisfy the equation: 1.4&#x2266;X/Y&#x2266;3.5, the present invention reduces the surface asperities of the substrate and prevents a micro short-circuit resulting from the piercing of the polymer electrolyte membrane of the fuel cell by the carbon fibers of the fabric so as to improve the characteristics of the fuel cell. In order to further prevent the piercing of the polymer electrolyte membrane by the carbon fibers of the gas diffusion layer substrate, the rough surface of the carbon fabric is smoothed by: (1) applying a clamping pressure of 1 to 20 kgf/cmto the contact area between each electrode and each conductive separator plate of the fuel cell; or (2) heating the gas diffusion layer surface before the gas diffusion layer is disposed onto the polymer electrolyte membrane.

Electrolyte film electrode union, fuel cell containing the same and process for producing them

A polymer dispersion type liquid crystal display element having liquid crystal droplets dispersed and held in a continuous matrix phase including polymer compound or a three dimensional network form of matrix including polymer compound dispersed between a pair of substrates, each having an inside electrode. The liquid crystal droplets are in all areas but for an area in the vicinity of the interfaces between the substrates. The liquid crystal droplets are ellipsoid of revolution forms of substantially the same size.

Macromolecular dispersion type liquid crystal display element and method of manufacturing the same

A polymer dispersion type liquid crystal (PDLC) display element comprising a complex of polymers and liquid crystal droplets held between a pair of substrates. The liquid crystal droplets are deformed into a compressed structure of their being contracted in a cell gap direction and an amount of deformation of the liquid crystal droplets is set to be in range in which a phenomenon of liquid crystal molecules rising up in the cell gap direction is not caused by excluded volume effects of the liquid crystals. The amount of deformation of the liquid crystal droplets, is set to be in range in which the phenomenon of liquid crystal molecules rising up in the cell gap direction is not caused by excluded volume effects of the liquid crystals can provide an increased tendency of the liquid crystal molecules to align in parallel to a phase boundary of the substrates. The DPLC display element having excellent threshold characteristics and scattering characteristics and high display characteristics can be achieved.

Polymer dispersion type liquid crystal display element, producing method therefor and apparatus for use in the producing method

A polymer dispersion type liquid crystal display element according to the invention is structured such that a complex of polymer and liquid crystal droplets is held between a pair of substrates. The liquid crystal droplets are deformed into a compressed structure of their being contracted in a cell gap direction and an amount of deformation of the liquid crystal droplets is set to be in range in which a phenomenon of liquid crystal molecules rising up in the cell gap direction is not caused by excluded volume effects of the liquid crystals. This construction that the amount of deformation of the liquid crystal droplets is set to be in range in which the phenomenon of liquid crystal molecules rising up in the cell gap direction is not caused by excluded volume effects of the liquid crystals can provide an increased tendency of the liquid crystal molecules to align in parallel to a phase boundary of the substrates. As a result of this, the polymer dispersion type liquid crystal display element having excellent threshold characteristics and scattering characteristics and high display characteristics can be achieved.

A method of making a polymer dispersion type liquid crystal display element including a phase separation step. The method calls for placing a liquid crystal polymer precursor compatible solution having a liquid crystal and a polymer precursor between a pair of substrates, each having an inside electrode, and irradiating a substrate surface with ultraviolet. The radiation causes a phase separation of the liquid crystal and the polymer precursor as well as polymerization and curing of the precursor. The method forms a polymer dispersion type liquid crystal having liquid crystal droplets dispersed and held in a continuous matrix phase or a three-dimensional network matrix. During the phase separation step, the irradiation time is controlled from the beginning of irradiation to the completion of phase separation to influence any of the degree of polymerization of the precursor in the solution, the rate of phase separation, and the generating density of the separated liquid crystal nuclei so that the dispersed liquid crystal droplets have even particle sizes.

A polymer dispersion type liquid crystal display element having a polymer dispersion type liquid crystal sandwiched between a pair of substrates, each having an inside electrode, is disclosed. The liquid crystal has liquid crystal droplets dispersed and held in either a polymer compound-containing continuous phase matrix or a three dimensional network of such a matrix. In one embodiment, the capacitance hysteresis, defined as Chys&equals;(C &minus;C )/C , does not exceed 1.5%. C is the capacitance for an applied voltage that is in the process of rising a voltage-capacitance characteristic; C is the capacitance of an applied voltage in the process of dropping; and C is the capacitance of a maximum applied voltage. In another embodiment, the Chys value does not exceed 0.6% when the optical hysteresis Thys is (P &minus;P )/P where P is the intensity of transmitted light of an applied rising voltage V, P is the intensity of transmitted light of an applied dropping voltage, and P is the intensity of transmitted light of a maximum applied voltage.

Growing community of inventors

Hyogo, Japan

Shinya Kosako