Jfe Chemical Corporation

Adchemco Corporation

Tetsuo Shiode

Ryuta Haga

Katsuhiro Nagayama

Makiko Ijiri

Hiromi Okamoto

Hidetoshi Morotomi

Masayasu Nagoshi

Takaaki Kondo

Kunio Miyazawa

Yasuhiro Mogi

Yasuyuki Takigawa

Kazuteru Tabayashi

Kenshi Noda

Shigeyuki Hirano

Syoji Komura

Yoshihiko Hase

Provided is a carbon material for a negative electrode of a lithium ion secondary battery, which has a small particle diameter, high initial charge-discharge efficiency, and a high 2 C discharge rate, and achieves both input-output characteristics and durability. Disclosed is a carbon material for a negative electrode of a lithium ion secondary battery, in which a 50% by volume particle diameter in a cumulative frequency distribution is 1.0 μm or more and less than 5.0 μm, a specific surface area by a BET method is 6.5 m/g or less, a tap density (D) is 0.70 g/cmor more, and a Raman R value obtained by Raman spectroscopy is more than 0.100 and less than 0.300, and the carbon material has a carbonaceous film on a surface of graphitized material particles of a mesophase microbead.

Carbon material for negative electrode of lithium ion secondary battery and method of producing the same, and negative electrode and lithium ion secondary battery using the carbon material

A method for producing an amorphous carbon particle includes the steps of: obtaining a first crosslinked product by admixing mesophase particles with an amorphous carbon precursor and thereafter subjecting the mixture to a crosslinking treatment, or obtaining a second crosslinked product by crosslinking the amorphous carbon precursor and thereafter admixing the mesophase particles with the crosslinked precursor; and subjecting the first or second crosslinked product to an infusibilization treatment and thereafter firing the product to produce amorphous carbon particles including the mesophase particles within the particles.

Method for producing amorphous carbon particle, amorphous carbon particles, negative electrode material for lithium ion secondary batteries, and lithium ion secondary battery

A method for producing amorphous carbon particles comprising includes adding and mixing graphite particles into a precursor of amorphous carbon and then cross-linking the precursor of amorphous carbon to obtain a first cross-linked product, or cross-linking a precursor of amorphous carbon and then adding and mixing graphite particles into the cross-linked precursor of amorphous carbon to obtain a second cross-linked product. Infusibility is imparted to the first or second cross-linked product to obtain an infusibilized product to which infusibility has been imparted. The infusibilized product is baked to obtain amorphous carbon particles. The amorphous carbon particles include the graphite particles and amorphous carbon which embeds the graphite particles.

Method for producing amorphous carbon particles, amorphous carbon particles, negative electrode material for lithium ion secondary battery, and lithium ion secondary battery

A method for producing a non-graphitizable carbon material includes providing a raw material of a non-graphitizable carbon material. The raw material is cross-linked to obtain a cross-linked product. The cross-linked product is infusibilized to obtain an infusibilized product. The infusibilized product is baked to obtain the non-graphitizable carbon material. A mechanochemical treatment is performed on the cross-linked product or the infusibilized product.

Method for producing non-graphitizable carbon material, negative electrode material for lithium ion secondary battery, and lithium ion secondary battery

Provided is a method for producing a non-graphitizable carbon material, the method including a step in which a raw material of the non-graphitizable carbon material is subjected to a cross-linking treatment to obtain a cross-linked product; a step in which the cross-linked product is subjected to an infusibility-imparting treatment to obtain an infusibility-imparted product; a step in which the infusibility-imparted product is subjected to a pulverizing treatment; and a step in which the infusibility-imparted product that has been subjected to the pulverizing treatment is fired at 900&#xb0; C. to 1300&#xb0; C. to obtain the non-graphitizable carbon material.

Method for producing non-graphitizable carbon material, non-graphitizable carbon material, negative electrode material for lithium-ion secondary battery, and lithium-ion secondary battery

Boron-substituted graphite, which contains N-bonded boron atoms in a small proportion relative to whole substituted boron atoms, is produced by heating a feed fine particulate mixture of an infusibilized carbonaceous material and a boron compound such that the carbonaceous material is carbonized into a carbon structure, raising a temperature of the resulting heated fine particulate mixture promptly to a graphitization treatment temperature in an inert atmosphere unreactive with boron, retaining the graphitization treatment temperature for a time sufficient to allow graphitization of the carbon structure to proceed to a desired extent, and then quickly cooling the resulting graphitized mixture. The boron-substituted graphite is useful as a negative electrode in a lithium-ion secondary battery.

Production process of material for lithium-ion secondary batteries, material obtained by the process, and batteries

A process is provided for the production of a carbonaceous material. The process comprises the following steps: subjecting a vacuum distillation residual pitch to heat treatment until the content of quinoline-insoluble components thereof becomes 50 to 85 wt. %, whereby the pitch is converted into a mesophase pitch; grinding the thus-obtained mesophase pitch into fine particles having an aspect ratio not greater than 2; subjecting the thus-ground product to oxidation treatment; and subjecting the thus-oxidized product to carbonization or graphitization treatment. A lithium ion secondary battery comprises a negative pole made of the carbonaceous material.

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Tokyo, Japan

Tetsuo Shiode