Mitsubishi Chemical Corporation

Tokai Carbon Company, Ltd.

Hideharu Satoh

Hitoshi Matsumoto

Keita Yamaguchi

Masakazu Yokomizo

Tadashi Ishihara

Nobuyuki Onishi

A negative electrode material for a nonaqueous secondary battery capable of realizing a nonaqueous secondary battery having a small charging/discharging irreversible capacity at an initial cycle and exhibiting an excellent high-rate charging/discharging characteristics and an excellent cycle performances is provided. The main component of the material is graphite particles. The median diameter is 5 &#x3bc;m or more, and 40 &#x3bc;m or less in the volume-basis particle size distribution based on the laser diffraction/scattering particle size distribution measurement. The tapping density is 0.7 g/cmor more. The specific surface area measured by a BET method is 0.2 m/g or more, and 8 m/g or less. The average circularity is 0.83 or more, and 1.00 or less. When an electrode is produced by a predetermined method for manufacturing an electrode and, the resulting electrode is subjected to X-ray diffraction, the graphite crystal orientation ratio I/Ion the electrode is 0.08 or more, where Irepresents the wide angle X-ray diffraction peak area of the (110) peak peak in the region of 2&#x3b8;=76.5 to 78.5 degrees of the graphite particles on the electrode and Irepresents the wide angle X-ray diffraction peak area of the (004) peak peak in the region of 2&#x3b8;=53.5 to 56 degrees.

Negative electrode material for nonaqueous secondary cells, negative electrode for nonaqueous secondary cells, and nonaqueous secondary cell

To provide a nonaqueous secondary battery ensuring that a charge-discharge irreversible capacity at an initial cycle is sufficiently small even when an active material layer comprising a negative electrode active material on a current collector is increased in a density for obtaining a high capacity. This object is attained by a graphite composite particle for a nonaqueous secondary battery, which satisfies the requirements (1) and (2):

Non-aqueous secondary battery-use graphite composite particle, cathode active substance material containing IT, cathode and non-aqueous secondary battery

A negative electrode for a nonaqueous electrolyte secondary battery having a small surface film resistance and a high negative electrode strength, wherein the negative electrode includes a collector and an active material layer formed thereon, wherein the active material layer contains an active material and a binder composition, wherein the active material is a material in which metal oxide fine particles having an average particle diameter of 250 nm or less are attached to the surface thereof, and wherein the binder composition contains a binder having an olefinic unsaturated bond.

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Ibaraki, Japan

Hideharu Satoh