Li2SiO3 Coating to Improve the High-voltage Performance of LiNi1/3Co1/3Mn1/3O2 Cathode

The poor high voltage performance of LiNi1/3Co1/3Mn1/3O2 (NCM) materials has become a main challenge for its practical application towards electric vehicles (EV). In this work, we develop a novel method to synthesize Li2SiO3-coated NCM cathode material and systematically investigate its high-voltage performance at 4.5 V. The results show that the Li2SiO3 coating layer cannot only prevent the cation disorder of the layered structure but also alleviate the interfacial reaction between the cathode and the electrolyte, leading to reduction of the charge transfer resistance and improvement of the kinetic performance. This cathode exhibits a capacity retention of 80.0 % after 200 cycles at room temperature and 87.6 % after 100 cycles at 45 °C, while the corresponding values of bare NCM are only 62.1 % and 81.4 %, respectively. In addition, the discharge specific capacities of Li2SiO3 coated NCM cathode at 2 C and 10 C could reach 154.4 and 104.4 mAh g-1, respectively.