Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Daido Metal Company Ltd.

Kuraray Chemical Co., Ltd.

Other

No-Tape Industrial Co., Ltd.

Tdk Corporation and Honda Motor Co., Ltd.

Nippon Chemi-Con Corporation

Kashima Oil Co., Ltd.

Shigeki Oyama

Manabu Iwaida

Kenichi Murakami

Kouki Ozaki

Masanori Tsutsui

Minoru Noguchi

Kenji Sato

Takeshi Fujino

Naohiko Oki

Hiroto Kobayashi

Shushi Nishimura

Yuji Kawabuchi

Hiroyuki Saito

Hideharu Iwasaki

Kiyonori Hinoki

Koichi Yoshida

Takehiko Sasaki

Kazutoshi Emoto

Nozomu Sugo

Tsuyoshi Ichiki

Toshiaki Fukushima

Tomohiko Kawaguchi

Mitsunori Hitomi

Yasuhiro Matsumoto

Kiyoto Otsuka

Takashi Maeda

Takashi Higono

Takanori Kitamura

Teruhiro Okada

Akiko Toriumi

Tatsuo Morotomi

Tsuyoshi Kowaka

Takahiro Haga

Makoto Ue

Yasushi Ohura

Morinobu Endoh

In activated carbon obtained by subjecting a carbonaceous material to an activation treatment, the overall content of alkali metals is set at 100 ppm or less, or the overall content of heavy metals is set at 20 ppm or less and the overall content of alkali metals is set at 200 ppm or less. In cases where such activated carbon is used as a raw material in electronic devices, the formation of dendrites by the reductive deposition of alkali metals or heavy metals tends not to occur, so that problems such as short-circuiting or the like tend not to arise, and a good rate of self-discharge retention is shown.

Activated carbon, method for production thereof, polarizing electrode and electrical double layer capacitor

Activated carbon useful as polarizable electrode material for an electric double-layer capacitor can be obtained by mixing a carbonaceous material and an alkali metal hydroxide while maintaining a solid state, granulating the obtained mixture while maintaining its solid state, dehydrating the obtained granulated substance while maintaining its solid state, and subjecting the granulated dehydration product obtained in the dehydration step to an activation treatment. The preferred pressure of the granulation treatment in the granulation step is 0.01 to 300 Torr, and the preferred temperature of the granulation treatment is 90 to 140&#xb0; C. The preferred pressure of the dehydration treatment in the dehydration step is 0.01 to 10 Torr, and the preferred temperature of the dehydration treatment is 200 to 400&#xb0; C.

Method for manufacturing activated carbon, polarizable electrode, and electric double-layered capacitor

A method is provided for optimizing the physical characteristics of a coating solution for an undercoat layer formed between a polarizable electrode layer and surface-roughened collector. A first step is carried out to form an undercoat layer on a collector whose surface has been roughened, and a second step is carried out to form a polarizable electrode layer on the undercoat layer. The first step is performed by coating the collector with a coating solution for the undercoat layer that includes electroconductive particles, a binder, and a solvent; the viscosity of the coating solution for the undercoat layer is set to from 0.15 to 0.75 Pa&#xb7;s, and the weight ratio (P/B) of the electroconductive particles (P) and binder (B) is set to from 20/80 to 40/60. The coating area of the undercoat layer can thereby be adjusted with high precision, and the resistance of the undercoat layer can be reduced.

Method for producing electrochemical capacitor electrode

A method is provided for optimizing the physical characteristics of a coating solution for a polarizable electrode layer formed on a collector. A first step is carried out to prepare a coating solution that includes porous particles, a fluorine-based binder, a good solvent that dissolves said fluorine-based binder, and a poor solvent that does not dissolve said fluorine-based binder. A second step is carried out to coat a collector with said coating solution to form the polarizable electrode layer on the collector. The viscosity of said coating solution for the polarizable electrode layer is set to between 0.5 to 3.5 Pa&#xb7;s and a weight ratio (GS/PS) of said good solvent (GS) and said poor solvent (PS) is set to between 60/40 to 80/20. The occurrence of cracks in the polarizable electrode layer and large nonuniformities in the thickness of the polarizable electrode layer can thus be prevented.

A method of making a polarizable electrode for an electric double layer capacitor, includes adding a binder assistant to a binder so that the binder is swollen and mixing a carbonaceous powder, a conductive assistant and thereafter the swollen binder, thereby obtaining a material mixture, kneading the material mixture into a primary forming material, forming the primary forming material into a secondary forming material, and rolling the secondary forming material into a sheet shape.

Method of making polarizable electrode for electric double layer capacitor

A sheet electrode with a predetermined thickness for an electric double layer capacitor is made by carrying out a roller rolling step in which a long sheet intermediate is made from a material containing a carbonaceous powder, a conductive assistant and a binder and thereafter. The sheet intermediate is passed between a pair of rolling rollers to be wound up by a winding section while being drawn out of a drawing section. The roller rolling step includes drawing the sheet intermediate out of the drawing section under a predetermined tension applied to the sheet intermediate, and controlling a widthwise position of the sheet intermediate immediately before the rolling rollers by an edge position controller, and winding the sheet intermediate rolled by the rollers onto a winding section while the winding section is applying a predetermined pressure to a rolling side drive roller located adjacent to the winding section and rotated at a predetermined speed.

Method of making sheet electrode for electric double layer capacitor and roller rolling machine suitable for use therein

To produce activated carbon for an electrode of an electric double-layer capacitor, the following steps are carried out sequentially: a step of subjecting a massive mesophase pitch to a pulverizing treatment to provide a pulverized powder; a step of subjecting the pulverized powder to an infusibilizing treatment under conditions of a temperature in a range of 300&#xb0; C. (inclusive) to 450&#xb0; C. (inclusive) in the atmospheric air current, a step of subjecting the pulverized powder to a carbonizing treatment under conditions of a temperature in a range of 600&#xb0; C. (inclusive) to 900&#xb0; C. (inclusive) in an inert gas current to provide a carbonized powder, a step of subjecting the carbonized powder to an alkali activating treatment under conditions of a temperature in a range of 500&#xb0; C. (inclusive) to 1,000&#xb0; C. (inclusive) in an inert gas atmosphere, followed by the post treatments, thereby producing alkali-activated carbon, and a step of subjecting the alkali-activated carbon to a pulverizing treatment. If an electrode is produced using the activated carbon, the electrode density can be increased.

Method for producing activated carbon for electrode of electric double-layer capacitor

In an electrode for an electric double layer capacitor of the present invention, the peak value of particle size distribution of graphite particles added to a conductive adhesive is in a range of 2.6 to 3.2 &#x3bc;m, not less than 100,000 dimples having a largest outer diameter in a range of 4 to 10 &#x3bc;m and a depth in a range of 4 to 15 &#x3bc;m are formed on the surface of the collector sheet per 1 cm, and the occupied area of the dimples to the entire surface area of the collector sheet is not more than 50%. By determining the saponification value of polyvinylalcohol which is used as a binder component of the conductive adhesive in a range of 90.0 to 98.5, adhesiveness of the collector sheet and the electrode forming sheet is improved. Furthermore, by substituting H atoms contained in the polyvinylalcohol with Si atoms, adhesiveness of the collector sheet and the electrode forming sheet can be further improved.

Electrode for electric double layer capacitor

A container for a long electrode sheet for electric double layer capacitor includes a cover closing the opening of the container body, a sealing member sealing a gap between the container body and the cover, a stem fixed to either the container body or the cover so that a bobbin is mounted thereon and formed with a male thread, a bobbin fixing unit including a fastening member having a female thread hole, and a holding unit including two presser plates, the female thread hole of the fastening member being threadedly engage with the male thread of the stem so that the presser plates are fastened thereby to be fixed, the holding unit holding the electrode sheet so as to prevent the electrode sheet from being detached from the bobbin by pressing two ends of electrode sheet.

Roll container with presser plates

An electrode sheet of an electric double layer capacitor is produced by using granules for formation of an electrode of an electric double layer capacitor which are obtained by kneading and then crushing materials including an activated material, a conductive filler, and a binder at 50 to 97 mass-%, 1 to 30 mass-%, and 2 to 20 mass-%, respectively, and which are essentially granules whose diameter is in a range of 47 to 840 &#x3bc;m. A method for manufacturing a sheet-like electrode by mixing and kneading materials including an activated carbon, carbon black, and PTFE into a kneaded material, producing a forming material by converting the kneaded material into granules, and forming and rolling the forming material.

Granules for formation of an electrode of an electric double layer capacitor, manufacturing method thereof, electrode sheet, polarized electrode, and electric double layer capacitor using a polarized electrode

A polarizing electrode for an electric double layer capacitor has good moldability and is capable of achieving higher density of electrode and higher capacity. An electric double layer capacitor employs the same. The polarizing electrode for an electric double layer capacitor is made of an activated carbon obtained by activating a hard-to-graphitize material (for example, phenol resin) with water vapor, and the activated carbon has a median particle size within a range from 4 &#x3bc;m to 8 &#x3bc;m in the particle size distribution as measured by a laser diffraction method and a benzene adsorption ratio of not less than 47.0% and not more than 60% by weight of activated carbon.

Polarizing electrode for electric double layer capacitor and electric double layer capacitor therewith

A process for producing an electrode for an electric double layer capacitor in which an alcohol based solvent which is a forming aid agent added during preparation of an electrode forming sheet is contained in the electrode forming sheet, and the electrode forming sheet and the collector sheet are joined without removing the solvent. Furthermore, a process for producing an electrode for an electric double layer capacitor in which an alcohol based solvent is added to the electrode forming sheet just before the joining process of the electrode forming sheet and the collector sheet.

Process for production of electrode for electric double layer capacitor

A carbonized productused for production of activated carbon for an electrode of an electric double-layer capacitor, includes a plurality of crystalliteseach having a graphite structure in an amorphous carbon matrixThe interlayer distance dof the crystallitesis set a value equal to or larger than 0.347 nm. Thus, by using this carbonized product, it is possible to produce activated carbon having a high electrostatic capacity density (F/cc) for an electrode of an electric double-layer capacitor.

Carbonized product used for production of activated carbon for electrode of electric double-layer capacitor

In an electrode drying process in which the electrode is molded in a sheet shape by kneading activated carbon powder, a binding material and an organic solvent for lubrication and a polarizing property electrode is formed by heating and removing the organic solvent for lubrication in the molded electrode, the organic solvent for lubrication included in the electrode is removed in a state in which the above electrode is widened in the sheet shape. In a manufacturing method of an electrode sheet for the electrical double layer capacitor, continuous drying and vacuum drying are performed in a drying process.

Polarizing property electrode for electrical double layer capacitor and manufacturing method of polarizing property electrode for electrical double layer capacitor, and manufacturing method of electrode sheet for electrical double layer capacitor

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Saitama, Japan

Shigeki Oyama