Jx Nippon Oil Energy Corporation

Eneos Corporation

Nippon Oil Company

Nippon Oil Corporation

Noriyuki Kiuchi

Keizo Ikai

Masaki Fujii

Shinya Taguchi

Takashi Suzuki

Takahiro Shirai

Hiroshi Kawachi

Takashi Maeda

Mitsuo Karakane

Hiroshi Kato

Tsutomu Nakamura

Takefumi Kohno

Kiwamu Takeshita

Yoshio Soda

Kunihiko Satou

Masaaki Shinagawa

Kazuhiro Igarashi

Provided is a synthetic graphite material, in which a size L (112) of a crystallite in a c-axis direction as calculated from a (112) diffraction line obtained by an X-ray wide angle diffraction method is in a range of 4 to 30 nm, a surface area based on a volume as calculated by a laser diffraction type particle size distribution measuring device is in a range of 0.22 to 1.70 m/cm, an oil absorption is in a range of 67 to 147 mL/100 g, and a half width Δvof a peak present in a wavelength range of 1580 cm±100 cmis in a range of 19 to 24 cmin Raman spectrum analysis using argon ion laser light having a wavelength of 514.5 nm.

Synthetic graphite material, synthetic graphite material production method, negative electrode for lithium ion secondary battery, and lithium ion secondary battery

A synthetic graphite material, in which a size L () of a crystallite in a c-axis direction as calculated from a () diffraction line obtained by an X-ray wide angle diffraction method is in a range of 4 to 30 nm, a surface area based on a volume as calculated by a laser diffraction type particle size distribution measuring device is in a range of 0.22 to 1.70 m/cm, an oil absorption is in a range of 67 to 147 mL/100 g, a spectrum derived from carbon appearing in an electron spin resonance method as measured using an X band is in a range of 3200 to 3410 gauss, and ΔHpp, which is a line width of the spectrum as calculated from a first derivative spectrum of the spectrum at a temperature of 4.8K, is in a range of 41 to 69 gauss.

The present invention provides a method for producing an activated carbon for an electric double layer capacitor, with which the wettability of a carbon material with an alkali activator is improved, thereby improving contact efficiency between the carbon material and the alkali activator and efficiently promoting reaction between the carbon material, which is a starting material and the activator. The method comprises adjusting a carbon material as it is or after having been calcined to produce a carbon powder having an average particle diameter of 0.5 to 15 &#x3bc;m, oxidizing the carbon powder to contain 3 percent by mass or more of oxygen, and activating the oxidized product with an alkali activator.

Activated carbon for electric double layer capacitor electrode and method for producing the activated carbon

Provided is a method for producing an activated carbon for an electric double layer capacitor electrode comprising adjusting a carbon material (including a calcined product of a carbon material) in particle size, followed by mixing the carbon material with an alkali activator, and then activating the mixture, wherein the mixing is carried out so that the particle size distribution composed of particles with a size of 300 &#x3bc;m or greater in the mixture of the carbon material and alkali activator is 5 percent or less so that the mixing state of the carbon material and alkali activator can be improved, resulting in a reduction in the ratio of the alkali activator.

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

A method for preparing a carbon/carbon composite material which is characterized in that a carbon preform is impregnated with a carbonaceous pitch exhibiting a densification parameter of 0.1 or more, said densification parameter being represented by the following formula (1), and then subjected to an isotactic compression at a pressure higher than the atmospheric pressure but not higher than 10 Kgf/cm.sup.2 and at a sintering temperature of 250.degree. to 3,000.degree. C., thereby densifying the carbon preform: Densification parameter={(Weight of a sintered carbonaceous pitch (hereinafter, referred to simply as a sintered product) to be obtained through a process where a carbonaceous pitch in an open-type container is heated from room temperature up to 1000.degree. C. at a rate of 2.degree. C./min., and then sintered for 2 hours at 1000.degree. C. under isotactic compression of 9.5 Kgf/cm.sup.2)}/(Weight of a carbonaceous pitch before being sintered).times.{(Bulk density of the sintered product in the open-type container)/(True density of the sintered product)}. . . (1).

Method for preparing a carbon/carbon composite material

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Tokyo, Japan

Noriyuki Kiuchi