Effects of Li2SiO3 coating on the performance of LiNi0.5Co0.2Mn0.3O2 cathode material for lithium ion batteries

Layered LiNi0.3Co0.2Mn0.3O2 (NCM523) material has been functionally coated with a uniform and thin layer of Li2SiO3 via a two-step method. Owing to its high lithium ion conduction and excellent structural stability against electrolyte decomposition, Li2SiO3 could greatly improve the Li+ ion diffusion rate and ameliorate the electrochemical capability of the layered oxide materials. Electrochemical tests illustrate that Li2SiO3 used as a Li+-ion conductor greatly improves electrochemical performance of the NCM523 cathode at high current density under high cutoff voltage. Particularly, the Li2SiO3-modified sample delivers an initial capacity of 140.0 mAh g(-1) and remains 134.1 mAh g(-1) even at a high current density of 10 C after 100 cycles, while the capacity of the pristine decreased sharply to 81.5 mAh g(-1). The capacity retention of Li2SiO3-modified NCM523 is 96.1%, while only 55.3% for the bare sample. This result demonstrates an efficient method for the Li2SiO3-modified NCM523 cathode with enhanced electrochemical performance, which has a certain reference for other cathode materials of Li-ion batteries. (C) 2016 Elsevier B.V. All rights reserved.