NEGATIVE ELECTRODE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, COMPOSITE NEGATIVE ELECTRODE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, RESIN COMPOSITION FOR LITHIUM ION SECONDARY BATTERY NEGATIVE ELECTRODE, NEGATIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY, AND LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a negative electrode material for a lithium ion secondary battery capable of securing high charging and discharging capacity, excellent initial charge/discharge characteristics and the excellent capacity maintenance rate, and also to provide a composite negative electrode material for a lithium ion secondary battery, a resin composition for a lithium ion secondary battery negative electrode, and a negative electrode for a lithium ion secondary battery.SOLUTION: The surface of a nuclear particle made of silicon whose average particle diameter is 5 nm or more and 100 nm or less is covered with a coating layer, a negative electrode material in which a silicon oxide is not substantially contained in the coating layer or a composite negative electrode material for a lithium ion secondary battery containing the negative material and a matrix material is used, and furthermore a polyimide resin as a binding resin or a precursor thereof is used, thereby capable of accomplishing high charging and discharging capacity, the excellent capacity maintenance rate and high initial efficiency.