Metal-graphite composite particles for negative electrode of lithium ion secondary battery and manufacturing method thereof, negative electrode material and negative electrode for lithium ion secondary battery, and lithium ion secondary battery

摘要

PPROBLEM TO BE SOLVED: To provide a cathode material for a lithium ion secondary battery, having a proper balance for battery characteristics, such as superior discharge capacity, high initial charging and discharging efficiency, and superior cycle characteristics, and to provide the cathode for the lithium ion secondary battery, the lithium ion secondary battery, and a metal-graphite composite particle which serves as its base. PSOLUTION: The metal-graphite composite particle contains a metal, capable of alloying with Li, a fibrous graphitic material, a non-fibrous graphitic material, and a carbonaceous material, the metal content is 1 wt.% or higher and lower than 30 wt.% based on the composite particle, and the fibrous graphitic material content is lower than 50 wt.% based on the graphitic material, the metal-graphitic based composite particle of which the vacancy factor is 25 to 80%, the cathode material for the lithium ion secondary battery, the cathode, and the lithium ion secondary electrode that uses the cathode are provided. PCOPYRIGHT: (C)2007,JPO&INPIT