ACTIVE MATERIAL FOR NEGATIVE ELECTRODE, NEGATIVE ELECTRODE COMPRISING THE SAME, LITHIUM SECONDARY BATTERY AND PREPARATION METHOD THEREOF

摘要

PURPOSE: A negative electrode active material is provided to improve the high voltage performance of a lithium secondary battery by comprising a rod-type lithium titanate. CONSTITUTION: A negative electrode active material comprises a lithium titanate. The area ratio of [111] plane of X-ray diffraction peak in the region a diffraction angle 2Θ is in 18.3°± 0.4 to [311] plane of X-ray diffraction peak in the region a diffraction angle 2Θ is in 35.5°± 0.4 is 2.2-5.5. The lithium titanate is a rod-type lithium titanate and has an aspect ratio of 1.5 or more and an average length of a short axis of 20-150 nm and an average length of a long axis is 250-950 nm. The negative electrode comprises the negative electrode active material.