NEGATIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY

摘要

The present invention provides a negative electrode active material which can prevent reduction in battery capacity by suppressing reaction of an electrolyte solution at the surface of the negative electrode active material as well as can reduce resistance resulting from the formation of a film. A negative electrode active material 90 for a lithium ion secondary battery comprises a carbon material 92 capable of reversibly storing and releasing lithium, an amorphous carbon membrane 94 coating the surface of the carbon material and a film 96 containing a phosphate compound and coating the surface of the amorphous carbon membrane.