Hitachi Chemical Company, Ltd.

Other

Hitachi, Ltd.

Sanyo Electric Co., Ltd.

Kouichi Takei

Yasuhisa Aono

Hidetoshi Honbo

Yasushi Muranaka

Seiji Takeuchi

Juichi Arai

Junya Kaneda

Noriyuki Watanabe

Manabu Kobayashi

Tatsuya Nishida

Masayuki Terasaka

Nobuaki Takane

Youichi Machii

Hideyuki Inomata

Yoshihiro Shoji

Hiroshi Nakagawa

Hiroki Terasaki

Yutaka Honda

Kiyoshi Suzuki

Toshikatsu Shimazaki

Katsuya Imai

Hidekuni Banno

Noriyuki c/o Hitachi Ltd Intellectual Property Group Watanabe

Yasuhisa c/o Hitachi Ltd Intellectual Property Group Aono

Junya c/o Hitachi Ltd Intellectual Property Group Kaneda

Seiji c/o Hitachi Ltd Intellectual Property Group Takeuchi

Yasushi c/o Hitachi Ltd Intellectual Property Group Muranaka

Artificial graphite particles, having a secondary particle structure in which a plurality of primary particles composed of graphite are clustered or bonded together, and having a layer structure in which the edge portion of the primary particles is bent in a polyhedral shape.

Artificial graphite particles and method for manufacturing same, nonaqueous electrolyte secondary cell negative electrode and method for manufacturing same, and lithium secondary cell

In order to provide a nonaqueous electrolyte secondary battery negative electrode material that has an excellent discharging capacity, the charge/discharge efficiency and the charge load characteristics, a manufacturing method thereof, a nonaqueous electrolyte secondary battery negative electrode with the negative electrode material and a nonaqueous electrolyte secondary battery, the invention provides a nonaqueous electrolyte secondary battery negative electrode material including graphite particles that have a block-like structure where a plurality of flat graphite fine particles assembles or bonds non-parallel with each other, the aspect ratio of 5 or less and a volume of fine pores in the range of 10 to 10nm in a volume of 400 to 2000 cm/kg; and a layer of carbon formed on a surface of the graphite particle, wherein a ratio (by weight ratio) of the layer of carbon to the graphite particle is in the range of 0.001 to 0.01, a manufacturing method thereof, a nonaqueous electrolyte secondary battery negative electrode with the negative electrode material and a nonaqueous electrolyte secondary battery.

Non-aqueous electrolyte secondary battery-use cathode material, production method therefor, non-aqueous electrolyte secondary battery-use cathode and non-aqueous electrolyte secondary battery using the cathode material

Artificial graphite particles and method for manufacturing same, nonaqueous electrolyte secondary cell, negative electrode and method for manufacturing same, and lithium secondary cell

A lithium secondary battery, which comprises a positive electrode, a negative electrode containing a lithium ion-storable/dischargeable negative electrode-active material and a lithium ion conductive, non-aqueous electrolytic solution or polymer electrolyte can have distinguished charging/discharging characteristics and a higher safety, when the negative electrode material contains particles comprising carbonaceous materials and at least one of elements capable of forming a compound with Li; the elements have a melting point of at least 900&#xb0; C. and a thermal expansion coefficient of not more than 9 ppm/K at room temperature; the particles are embedded in a plurality of layers of the carbonaceous materials; the particles being subjected to a mechanical treatment to make particle sizes of the particles smaller than the initial particle size in advance.

Lithium secondary battery, and process for producing the same

A lithium secondary battery, which comprises a positive electrode, a negative electrode containing a lithium ion-storable/dischargeable negative electrode-active material and a lithium ion conductive, non-aqueous electrolytic solution or polymer electrolyte can have distinguished charging/discharging characteristics and a higher safety, when the negative electrode material contains particles comprising carbonaceous materials and at least one of elements capable of forming a compound with Li; the elements have a melting point of at least 900&deg; C. and a thermal expansion coefficient of not more than 9 ppm/K at room temperature; the particles are embedded in a plurality of layers of the carbonaceous materials; the particles being subjected to a mechanical treatment to make particle sizes of the particles smaller than the initial particle size in advance.

A silica glass production process that can prevent cracks from occurring during the step of gel drying. In a process for producing silica glass, comprising the steps of subjecting a partial polycondensation product of alkoxysilane to hydrolysis in the presence of a solvent, an organic polymeric compound and a basic catalyst to form a sol, making the sol into a gel, drying the gel to form a dry gel, and firing the dry gel to obtain a glass, a salt is caused to exist in a concentration not less than 1.times.10.sup.-4 mol based on 100 g of the partial polycondensation product of alkoxysilane in the step of subjecting the partial polycondensation product of alkoxysilane to hydrolysis to form a sol.

Process for producing silica glass

Growing community of inventors

Hitachi, Japan

Kouichi Takei