Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Takayuki Fukai

Masataka Takeuchi

Yuuichi Kamijou

Yasuaki Wakizaka

Chiaki Sotowa

Yoshiyuki Nishimura

Ryusuke Miura

Akinori Sudoh

Masako Tanaka

Yoshishige Sekiguchi

Hiroyuki Yamashita

Osamu Kanazawa

Masao Todoriki

A graphite material having pores which, when 200 rectangular regions of 6 &#x3bc;m&#xd7;8 &#x3bc;m are randomly selected in a surface image of the graphite material observed by a scanning electron microscope, in the surface of the graphite material appearing in the regions, a pore appearing on the surface and having an aperture in a shape having a diameter of 15 nm to 200 nm, a circularity degree of 0.75 to 1.0 and a major axis/minor axis ratio of 1.0 to 1.5 is visible in two regions or more. Also disclosed is a carbon material for battery electrodes, a paste for electrodes, an electrode and a lithium ion secondary battery including the graphite material.

Graphite material, carbon material for battery electrode, and battery

A method for producing a graphie material for an electrode material for lithium ion batteries, including a step for exothermically graphitizing a carbon material by directly passing an electric current therethrough. The carbon material has an compact powder resistivity of 0.4 &#x3a9;&#xb7;cm or less when compressed to a density of 1.4 g/cm, has an angle of repose in the range of 20&#xb0; to 50&#xb0; inclusive, and has a particle size (D90) in the volume-based particle size distribution measured using laser diffraction of 120 &#x3bc;m or less. The average surface interval (d002) of a surface (002) of the carbon material after graphitization, measured using x-ray diffraction, is in the range of 0.3354 nm-0.3450 nm inclusive.

Method for producing electrode material for lithium ion batteries

A method for producing a graphite material for lithium ion batteries, including a step for exothermically graphitizing a carbon material by directly applying an electric current therethrough. The carbon material is obtained by heating at a temperature in the range of 800&#xb0; C.-1500&#xb0; C. inclusive and subsequently pulverizing an organic carbon starting material, has a compact powder resistivity of 0.3 &#x3a9; cm or less when compressed to a density of 1.4 g/cm, has an angle of repose in the range of 20&#xb0; to 50&#xb0; inclusive, and has a particle size (D90) in the volume-based particle size distribution measured using laser diffraction of 120 &#x3bc;m or less. The average surface interval (d002) of a surface (002) of the carbon material after graphitization, measured using x-ray diffraction, is in the range of 0.3354 nm-0.3450 nm inclusive.

In order to prevent the rupturing of a graphite electrode comprising electrode sections joined with one another by a socket and a nipple, electrical insulating material is applied on the joined surfaces to decrease the current across the nipple.

Graphite electrode having joints

Growing community of inventors

Tokyo, Japan

Takayuki Fukai