Coating of LiNi_1/3Mn_1/3Co_1/3O₂ cathode materials with alumina by solid state reaction at room temperature

Abstract

Alumina coated LiNi_1/3Mn_1/3Co_1/3O₂ particles were obtained by a simple method of solid state reaction at room temperature. The reaction mechanism of solid state reaction at room temperature was investigated. The structure and morphology of the coating materials were investigated by XRD, SEM and TEM. The electrochemical performances of uncoated and Al₂O₃-coated LiNi_1/3Co_1/3Mn_1/3O₂ cathode materials were studied within a voltage window of 3.00–4.35 V at current density of 30 mA/g. SEM, TEM and EDS analytical results indicate that the surface of LiNi_1/3Mn_1/3Co_1/3O₂ particles is coated with very fine Al₂O₃ composite, which leads to the improved cycle ability though a slight decrease in the first discharge capacity is observed. It is proposed that surface treatment by solid state reaction at room temperature is a simple and effective method to improve the cycle performance of LiNi_1/3Co_1/3Mn_1/3O₂ particles.

Keywords

solid state reaction / preparation / electrochemical property / LiNi_1/3Mn_1/3Co_1/3O₂ / alumina / coating