NEGATIVE ELECTRODE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, METHOD FOR PRODUCTION THEREOF, NEGATIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY, AND LITHIUM ION SECONDARY BATTER

摘要

Disclosed is a negative electrode material for a lithium ion secondary battery which comprises a composite material (A), wherein the composite material (A) comprises a graphitic material and a silicon particle closely adhered onto the graphitic material, and the silicon particle has a coating (A) comprising a carbonaceous material (A) on substantially the entire surface area thereof. The negative electrode material has high adhesion between the metal particles or between the metal particle and the carbonaceous material, and does not cause the separation between the metal particles or between the metal particle and the carbonaceous material by the expansion/contraction caused by charge-discharge cycles. Therefore, the negative electrode material can be used for a negative electrode for a lithium ion secondary battery, and enables to provide a lithium ion secondary battery having high discharge capacity, excellent cycle properties and excellent initial charge-discharge efficiency. ® KIPO & WIPO 2009