Li₂SiO₃ Coating to Improve the High-voltage Performance of LiNi_1/3Co_1/3Mn_1/3O₂ Cathode

摘要

The poor high voltage performance of LiNi1/3Co1/3Mn1/3O2 (NCM) materials has become a mainchallenge for its practical application towards electric vehicles (EV). In this work, we develop a novelmethod 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 thecation disorder of the layered structure but also alleviate the interfacial reaction between the cathodeand the electrolyte, leading to reduction of the charge transfer resistance and improvement of thekinetic performance. This cathode exhibits a capacity retention of 80.0 % after 200 cycles at roomtemperature and 87.6 % after 100 cycles at 45 C, while the corresponding values of bare NCM areonly 62.1 % and 81.4 %, respectively. In addition, the discharge specific capacities of Li2SiO3 coated-1 NCM cathode at 2 C and 10 C could reach 154.4 and 104.4 mAh g , respectively.