NEGATIVE ELECTRODE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, NEGATIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY USING THE NEGATIVE ELECTRODE MATERIAL, AND LITHIUM ION SECONDARY BATTERY

摘要

Disclosed are: a lithium ion secondary battery having a smaller irreversible capacity compared with those of conventional lithium ion secondary batteries and excellent input/output properties and service life properties; a negative electrode material for a lithium ion secondary battery, which enables the production of the above-mentioned lithium ion secondary battery; and a negative electrode for a lithium ion secondary battery, which is produced using the negative electrode material. Specifically disclosed is a negative electrode material for a lithium ion secondary battery, which comprises a carbon material that serves as a core and a carbon layer formed on the surface of the carbon material, wherein (A) the carbon face (002) has a face distance of 3.40 to 3.70 Å as determined by an XRD measurement, (B) the content ratio (by mass) of the carbon layer to the carbon material is 0.005 to 0.1, (C) the specific surface area is 0.5 to 10.0 m2/g as determined by a nitrogen adsorption measurement at 77K, and (D) the specific surface area (Y) as determined by carbon dioxide adsorption at 273K and the content ratio (by mass) (X) of the carbon layer to the carbon material meet the requirement represented by formula (I): 0 < Y < AX+2.5 [wherein A = 100].