CARBON BLACK COMPOSITE AND LITHIUM-ION SECONDARY BATTERY USING SAME

摘要

The present invention provides a conductive auxiliary agent capable of reducing the green compact resistance of a positive electrode material used for a lithium-ion secondary battery. A carbon black composite is provided in which a carbon black having a band ratio (D/G) of 1.10 or less and a fibrous carbon are linked with each other, where the band ratio represents the degrees of crystallinity (G-band) and defect (D-band) in the Raman spectroscopy. It is preferable that the specific surface of the carbon black is smaller than the specific surface of the fibrous carbon and is 10 to 60 m2/g. It is preferable that the fibrous carbon is a carbon nanotube having a fiber diameter of 5 to 50 nm and a specific surface of 50 to 400 m2/g. It is also preferable that the proportion between the fibrous carbon and the carbon black is 70 : 30 to 5 : 95 in mass ratio.