Nippon Oil Corporation

Nippon Petroleum Refining Company, Limited

Power Carbon Technology Co., Ltd.

Kiwamu Takeshita

Hideki Ono

Takashi Oyama

Tamotsu Tano

Masaki Fujii

Ippei Fujinaga

Kazuhisa Nakanishi

Hiromitsu Hashisaka

Keizou Ikai

Keiji Higashi

Keizo Ikai

Akio Sakamoto

Toshitaka Fujii

Takashi Noro

Hiroshi Kato

Shinya Taguchi

Tsutomu Nakamura

Yuichi Nakano

Noriyuki Kiuchi

Haruyoshi Mizuta

Tatsuji Maruyama

Kazuhiro Igarashi

Eiji Kitajima

Shiro Nakamo

The present invention provides a process of producing an activated carbon for an electric double layer capacitor, which can produce easily and inexpensively an activated carbon free from fusing of carbon particles during activation and having a small diameter, a uniform particle diameter, and a relatively large specific surface area on a commercial scale. The process comprises the steps of calcining an easily graphitizable carbon material so that the reduction rates of the hydrogen/carbon atomic ratio (H/C) and the volatile components in the carbon material are 4 percent or more and 5 percent or more, respectively after calcination and activating the carbon material thereby producing an activated carbon for an electric double layer capacitor, having an average particle diameter of 0.5 to 7 &#x3bc;m and a BET specific surface area of 1500 to 3000 m/g.

Process of producing activated carbon for electric double layer capacitor electrode

The present invention provides a raw coke having such a structure that the graphitized product resulting from graphitization of the raw coke at a temperature of 2800&#xb0; C. under an inactive gas atmosphere will have ratios of the crystallite size to the lattice constant of 360 or less in the (002) plane and 1500 or less in the (110) plane, as a raw coke providing active carbon produced by alkali-activating the raw coke, which is reduced in remaining alkali content and can simplify washing operation because washing liquid can easily pass through the activated carbon, or as a raw coke for the production of needle coke.

Raw coke for electricity storage carbon material and needle coke

The present invention provides feedstock compositions for use of the production of an activated carbon for electric double layer capacitor electrodes or the production of needle coke, comprising a first heavy oil with an initial boiling point of 300&#xb0; C. or higher, an asphalten content of 12 percent by mass or less, a saturate content of 50 percent by mass or more and a sulfur content of 0.3 percent by mass or less, produced as a residue resulting from vacuum-distillation of a petroleum-based oil and a second heavy oil with an initial boiling point of 150&#xb0; C. or higher and a sulfur content of 0.5 percent by mass or less, produced by subjecting a hydrocarbon oil to fluidized catalytic cracking.

Feedstock composition and raw coke for electricity storage carbon material and needle coke

The capacitance per volume of an electric double-layer capacitor can be increased by using a raw-material carbon composition for use in a carbon material for an electrode of the electric double-layer capacitor by applying an activation process, characterized in that the raw-material carbon composition has a volatile content of 1.3% by mass to 15% by mass (both inclusive), and microstrength of 5 to 30% when the volatile content is less than 6% by mass while microstrength of 5 to 20% when the volatile content is 6% or more.

Raw-material carbon composition for carbon material for electrode of electric double-layer capacitor

The present invention provides a raw material carbon composition that is converted to a carbon material for an electrode in an electric double layer capacitor that can develop a high level of electrostatic capacity with good reproducibility without producing any synthetic pitch. The raw material carbon composition is converted to a carbon material for an electrode in an electric double layer capacitor upon activation treatment and is characterized in that, when the raw material carbon composition is carbonized in an inert gas atmosphere at a temperature of 1000 to 1500&#xb0; C., the true relative density (RD) and the total hydrogen content (TH %) in the carbonized material obtained after the burning satisfy the following formula (1):RD=&#x2212;0.75TH %+intercept&#x2003;&#x2003;(1)wherein the intercept is 2.160 or greater.

Raw material carbon composition for carbon material for electrode in electric double layer capacitor

A method for producing activated carbon for electrodes of electric double layer capacitors is disclosed which comprises an activation step wherein activated carbon is obtained by mixing an alkali metal hydroxide with a carbon raw material for the activated carbon and heating the mixture in an inert gas atmosphere, a deactivation removal step wherein the alkali metal in the activated carbon is deactivated and removed, and a heat treatment step wherein the activated carbon having gone through the deactivation removal step is heated in an inert gas atmosphere at a temperature higher than 400&#xb0; C. but not higher than the heating temperature in the activation step. Also disclosed are activated carbon produced by such a method, activated carbon for electrodes of electric double layer capacitors wherein the alkali metal content is less than 100 mass ppm, activated carbon for electrodes of electric double layer capacitors having specific impedance characteristics, and activated carbon for electrodes of electric double layer capacitors having a specific amount of surface functional groups and a specific amount of surface carboxyl groups. In an electric double layer capacitor comprising a pair of electrodes and an electrolyte solution, at least one of the electrodes contains such an activated carbon.

Electric double layer capacitor, activated carbon for electrode therefor and method for producing the same

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Tokyo, Japan

Kiwamu Takeshita