Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Asahi Glass Company, Limited

Matsushita Electrical Industrial Co., Ltd.

Showa Shell Sekiyu K.k.

Panasonic Intellectual Property Management Co., Ltd.

Akihiko Yoshida

Atsushi Nishino

Makoto Uchida

Yoshihiro Hori

Yasushi Sugawara

Masaki Ikeda

Eiichi Yasumoto

Junji Morita

Osamu Sakai

Yasuo Mizuno

Teruhisa Kanbara

Hisaaki Gyoten

Yasuhiro Takeuchi

Akiyoshi Hattori

Masaki Yamauchi

Masao Yamamoto

Yasuo Takebe

Shinya Kosako

Ichiro Tanahashi

Junji Niikura

Nobuyuki Yoshiike

Yoshihiro Watanabe

Takeshi Yonamine

Mikiko Yoshimura

Hayashi Hayakawa

Kiyoaki Imoto

Yoichiro Tsuji

Hiroki Kusakabe

Masato Hosaka

Katsuyuki Fujito

Masahiro Hiraka

Seiji Nonaka

Masakatsu Sugai

Ichiro Aoki

Seiro Hasegawa

Takehiko Unoguchi

Kazuhito Hatoh

Hidenobu Wakita

Kunio Kimura

Soichi Shibata

Hisashi Kodama

Masaaki Aoki

Shinji Kinoshita

Hirokazu Wakabayashi

Toshikazu Tomioka

Takayuki Urata

Tsutomu Minami

Takahiro Umeda

Shinichi Arisaka

Hirokazu Tachibana

Yasuhiro Shindo

Hiroyuki Nakazumi

Haruhiko Handa

Masahiro Kawamura

Nobukuni Ogino

Atsushi Naito

Noboru Tohge

Teruo Namba

Handa Haruhiko

Kouzou Igarashi

Junichiro Umeda

Ichiroh Tanahashi

In a fuel cell system, during the state where the fuel cell system is not generating an electric power, a fuel gas passage and an oxidizing gas passage are closed, and an inert gas supply device () supplies an inert gas to an anode space () which is substantially isolated from outside, the anode space including the closed fuel gas passage and a space connected to the closed fuel gas passage, while an air supply device () supplies air to a cathode space () which is substantially isolated from outside, the cathode space including the closed oxidizing gas passage and a space connected to the closed oxidizing gas passage. With this, the fuel cell system is capable of achieving high energy efficiency and of surely preventing degradation of electrodes during the state where the fuel cell system is not generating the electric power, irrespective of repeated start-up and stop.

Fuel cell system

In a conventional polymer membrane electrode assembly, particularly when operated for a long period of time, a portion of the polymer electrolyte membrane to be in contact with the gas diffusion layer has suffered significant degradation. In order to address this, in a membrane electrode assembly including a hydrogen ion conductive polymer electrolyte membrane, a pair of catalyst layers arranged on both surfaces of the polymer electrolyte membrane, and a pair of gas diffusion layers, each including a fibrous substrate, arranged on the outer surfaces of the catalyst layers, a thickness Tof a center portion that faces the catalyst layer and a thickness Tof a peripheral portion surrounding the center portion are set to satisfy a expression (1):0.7&#x2266;&#x2266;0.9.

Membrane electrode assembly with a fibrous substrate, method for producing the same and polymer electrolyte fuel cell

To provide a polymer electrolyte membrane having excellent size stability and excellent mechanical strength that can sufficiently prevent the size change due to the swelling condition, the displacement of the polymer electrolyte membrane and the formation of wrinkles during the production of the polymer electrolyte fuel cell, and can prevent damage during the production and operation of the polymer electrolyte fuel cell. In a composite electrolyte membrane including a porous reinforcement layer made of a resin and an electrolyte layer made of a polymer electrolyte and laminated at least one main surface of the reinforcement layer, the direction having a high tensile modulus of elasticity in the reinforcement layer is substantially corresponded with the direction having a high rate of size change in the electrolyte layer.

Composite electrolyte membrane, catalyst-coated membrane assembly, membrane-electrode assembly and polymer electrolyte fuel cell

To provide a gas diffusion layer excellent in micro short-circuit resistance and anti-flooding characteristics by optimizing the surface shape of a gas diffusion layer. In a gas diffusion layer for a gas diffusion electrode including at least a catalyst layer containing an electrode catalyst and a gas diffusion layer having electron conductivity and gas diffusibility, a second surface of the gas diffusion layer, which is positioned opposite to a first surface thereof to be in contact with the catalyst layer, is made rougher than the first surface. The first surface has a maximum height Ryof 10 to 50 determined by JIS B 0601 surface roughness measurement method, and the second surface has a maximum height Ryof 100 to 500 determined by JIS B 0601 surface roughness measurement method.

Gas diffusion layer and fuel cell using the same

An object of the present invention is to provide a catalyst-coated membrane suitable for achieving a polymer electrolyte fuel cell that sufficiently prevents a decrease in the initial characteristics and also exhibits sufficient cell performance for a long period of time and has excellent durability. In at least the cathode catalyst layer, the ratio (W/W) of the weight of the polymer electrolyte (W) to the weight of the catalyst-carrying carbon (W) is decreased from an innermost layer positioned closest to the polymer electrolyte membrane toward an outermost layer positioned farthest from the polymer electrolyte membrane. The ratio (W/W) in the innermost layer is 0.8 to 3.0, and the ratio (W/W) in the outermost layer is 0.2 to 0.6.

Catalyst-coated membrane, membrane-electrode assembly, and polymer electrolyte fuel cell

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

The present invention provides a gas diffusion layer for a fuel cell which has proper rigidity, is easy to handle and contributes to the improvement of the productivity of fuel cells. A method for producing a gas diffusion layer for a fuel cell including a first step of: impregnating a conductive porous substrate made of a conductive carbon fiber cloth or conductive carbon fiber felt with a first dispersion containing a first fluorocarbon resin having thermoplasticity; and baking the first conductive porous substrate at a first baking temperature of not less than the melting point of the first fluorocarbon resin and less than the decomposition temperature of the first fluorocarbon resin to enhance the rigidity of the conductive porous substrate.

Gas diffusion layer, electrode and membrane electrode assembly for fuel cell, and production methods thereof

A polymer electrolyte fuel cell comprising: a hydrogen ion-conductive polymer electrolyte membrane; an anode and a cathode with the electrolyte membrane interposed therebetween; an anode-side conductive separator having a gas flow channel for supply of a fuel gas to the anode; and a cathode-side conductive separator having a gas flow channel for supply of an oxidant gas to the cathode, wherein each of the anode and the cathode comprises at least a catalyst layer in contact with the electrolyte membrane and a gas diffusion layer in contact with the catalyst layer and the separator, and at least one of the anode and the cathode contains a compound represented by the formula (I):R&#x2014;O&#x2014;{(CHO)&#x2014;(CHO)}&#x2014;R&#x2003;&#x2003;(I)where Rand Rare independent of each other and each represents a hydrogen atom or an alkyl group having not less than 5 and not more than 15 carbon atoms, n and m are integers which satisfy 0&#x2266;n&#x2266;5, 0&#x2266;m&#x2266;5 and 1&#x2266;n+m&#x2266;5, and when neither n nor m is 0, at least one of the ethylene oxide group and at least one of the propylene oxide group are arranged in a random fashion.

Polymer electrolyte fuel cell and production method of the same

In a polymer electrolyte fuel cell including a hydrogen ion conductive polymer electrolyte membrane; a pair of electrodes composed of catalyst layers sandwiching the hydrogen ion conductive polymer electrolyte membrane between them and gas diffusion layers in contact with the catalyst layers; a conductive separator plate having a gas flow channel for supplying a fuel gas to one of the electrodes; and a conductive separator plate having a gas flow channel for supplying an oxidant gas to the other electrode, in order to bring a hydrogen ion conductive polymer electrolyte and a catalyst metal of the catalyst layers containing the hydrogen ion conductive polymer electrolyte and conductive carbon particles carrying the catalyst metal sufficiently and uniformly into contact with each other, the polymer electrolyte is provided in pores of an agglomerate structure of the conductive carbon particles. Consequently, the reaction area inside the electrodes is increased, and higher performance is exhibited.

Polymer electrolyte fuel cell

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

Disclosed is a fuel cell comprising: a hydrogen-ion conductive polymer electrolyte membrane; a pair of electrodes sandwiching the hydrogen-ion conductive polymer electrolyte membrane; a first separator plate having a gas flow path for supplying a fuel gas to one of the electrodes; and a second separator plate having a gas flow path for supplying an oxidant gas to the other of the electrodes, wherein each of the electrodes has an electrode catalyst layer comprising at least a conductive carbon particle carrying an electrode catalyst particle and a hydrogen-ion conductive polymer electrolyte, the electrode catalyst layer being in contact with the hydrogen-ion conductive polymer electrolyte membrane, and at least one of the electrodes comprises a catalyst for trapping the fuel gas or the oxidant gas which has passed through the hydrogen-ion conductive polymer electrolyte membrane.

Polymer electrolyte fuel cell and production method thereof

A polymer electrolyte fuel cell is provided comprising: a hydrogen ion conductive polymer electrolyte membrane; an anode and a cathode sandwiching the hydrogen ion conductive polymer electrolyte membrane; an anode side electroconductive separator having a gas channel for supplying a fuel gas to the anode; a cathode side electroconductive separator having a gas channel for supplying an oxidant gas to the cathode; characterized in that the anode and the cathode comprise a gas diffusion layer and a catalyst layer formed on the gas diffusion layer at the side in contact with the hydrogen ion conductive polymer electrolyte membrane, the catalyst layer has catalyst particles and a hydrogen ion conductive polymer electrolyte, and at least either of hydrogen ion conductivity and gas permeability of at least either of the anode and the cathode varies in a thickness direction of the anode or the cathode.

Polymer electrolytic fuel cell and method for producing the same

A porous supporting carbon body of a gas diffusion layer is provided with a larger number of smaller pores at its catalyst layer side and a smaller number of larger pores at the other side, particularly with an appropriate distribution of finer mesh at its catalyst layer side and coarser mesh at the other side. As a result, a high performance polymer electrolyte fuel cell is obtained in which water generated at the catalyst layer is quickly sucked out to the gas diffusion layer, and is evaporated at the gas diffusion layer to be effectively exhausted to outside the fuel cell, so that excessive water can be prevented from retaining in the gas diffusion electrode, with the polymer electrolyte membrane being maintained at an appropriately wet condition.

Growing community of inventors

Hirakata, Japan

Akihiko Yoshida