Mitsubishi Chemical Corporation

Takashi Kameda

Hideharu Sato

Hideaki Tanaka

Tomohiro Sato

Iwao Soga

Nobuyuki Ishiwatari

Tooru Fuse

Shunsuke Yamada

Koichi Nishio

Satoshi Akasaka

Shingo Morokuma

Daigo Nagayama

Hiromitsu Ikeda

Tadashi Ishihara

A carbon material may include granulated particles satisfying (1L) and (2L):

Carbon material, method for producing carbon material, and non-aqueous secondary battery using carbon material

A carbon material for a non-aqueous secondary battery containing a graphite capable of occluding and releasing lithium ions, and having a cumulative pore volume at pore diameters in a range of 0.01 μm to 1 μm of 0.08 mL/g or more, a roundness, as determined by flow-type particle image analysis, of 0.88 or greater, and a pore diameter to particle diameter ratio (PD/d50 (%)) of 1.8 or less, the ratio being given by equation (1A): PD/d50 (%)=mode pore diameter (PD) in a pore diameter range of 0.01 μm to 1 μm in a pore distribution determined by mercury intrusion/volume-based average particle diameter (d50)×100 is provided.

A carbon material for nonaqueous-electrolyte secondary-battery negative electrode is provided, which satisfies the followings (1) and (2): (1) the carbon material has an aspect ratio of 10 or less; (2) the amount of CO eliminated from the carbon material during heating to 1,000&#xb0; C., as determined with a temperature programmed decomposition mass spectrometer (TPD-MS), is 2-15 &#x3bc;mol/g.

Carbon material for nonaqueous-electrolyte secondary-battery negative electrode and process for producing the same, negative electrode including the same for nonaqueous secondary battery, and nonaqueous-electrolyte secondary battery

A mixed carbon material is useful for an electrode of a nonaqueous secondary battery. The material has two component materials: carbon material A and carbon material B. Both materials have high capacity and rapid charge-discharge characteristics. Carbon material A, a multilayer-structure material containing an amorphous carbon covering the surface of a graphitic particle, has particularly excellent charging-discharging properties. Carbon material B has particularly excellent electrical conductivity properties. A battery with an electrode having the mixed carbon material can have both rapid charge-discharge characteristics and high cycle characteristics.

Negative electrode material for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery using the same

A negative electrode material for a nonaqueous electrolyte secondary battery, where the negative electrode contains a carbon material A and a carbon material B. Carbon material A is a multilayer-structure carbon material containing a graphitic particle having an amorphous carbon surface covering, where the interplaner spacing of 002 planes, by wide-angle XRD, is 3.37 &#x212b; or less, Lc is 900 &#x212b; or more, the tap density is 0.8 g/cmor more, and the Raman R value is from 0.25 to 0.6. Carbon material B is a graphitic particle where the interplanar spacing of 002 planes, by wide-angle XRD, is 3.37 &#x212b; or less, Lc is 900 &#x212b; or more, the tap density is 0.8 g/cmor more, the Raman R value is from 0.2 to 0.5, and the average degree of circularity, determined by a flow-type particle analyzer, is 0.9 or more.

A carbonaceous material has a plane space d002 of a (002) plane less than 0.337 nm in an X-ray wide angle diffraction method, a crystallite size (Lc) of 90 nm or higher, an R value, as a peak intensity ratio of a peak intensity of 1360 cm to a peak intensity of 1580 cm in a Raman spectrum in use of an argon ion laser, of 0.20 or higher, and a tap density of 0.75 g/cm or higher. Also disclosed is a multilayer structure carbonaceous material for electrode, which is manufactured by carbonizing some organic compounds where the carbonaceous material for electrode is mixed with the organic compounds. The battery using the carbonaceous material for electrode or the multilayer structure carbonaceous material for electrode has a large capacity, a small irreversible capacity admitted in the initial cycle, excellent capacity maintaining rate of the cycle, and particularly, largely improved quick charging and discharging characteristics.

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Ibaraki, Japan

Takashi Kameda