ANODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, METHOD OF MANUFACTURING ANODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, LITHIUM ION SECONDARY BATTERY, AND METHOD OF CHARGING LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide, e.g., a novel and improved anode active material for a lithium ion secondary battery which can increase the cycle life of the lithium ion secondary battery while maintaining the high discharge capacity of a silicon-based active material.SOLUTION: According to an aspect of the present invention for solving the problem, an anode active material for a lithium ion secondary battery is provided which contains: surface modified particles comprising silicon-based active material particles and a carbon material covering the surface of the silicon-based active material particles; and hard carbon conjugated with the surface modified particles. The silicon-based active material has a polycrystal, and the total mass of the carbon material is 0.35 to 3.5 mass% based on the total mass of the silicon-based active material particles and the carbon material.SELECTED DRAWING: Figure 1