NEGATIVE ELECTRODE ACTIVE MATERIAL AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, AND METHODS OF PRODUCING THE SAME

摘要

A negative electrode active material for use in a non-aqueous electrolyte secondary battery. The negative electrode active material is composed of a mixture of a silicon-contained material and a carbon material and capable of being doped with lithium and de-doped. Silicon contained in the silicon-contained material has a crystallite size of 10 nm or less. This crystallite size is calculated by a Scherrer method from a half width of a diffraction peak attributable to Si (220) in X-ray diffraction. This negative electrode active material can maintain a high usage rate of the silicon-contained material at the time of charging and discharging in a non-aqueous electrolyte secondary battery that uses the mixture of the silicon-contained material and the carbon material as the negative electrode active material.