Improving Cyclic Stability and Rate Performance of Lithium Ion Batteries Using La³⁺ Modified LiNi_0.6Co_0.2Mn_0.2O₂ Cathode Materials

Abstract

La₄NiLiO₈-coated NCM622 samples were prepared through a sol-gel method, and the electrochemical performance as cathode materials was investigated. It is revealed that part of the introduced La³⁺ ions produce a coating layer on the surface of NCM622 particles, while the rest occupy the 3b position of the lattice. The optimized sample exhibits a capacity retention of 96.54% after 100 cycles under 1C rate with a discharge specific capacity of 117.54 mAh·g⁻¹ under 5C rate, much higher than those of the unmodified sample. The results show that the addition of La³⁺ ion can greatly improve the cyclic stability and the rate performance of NCM622.

Keywords

lithium ion batter / La³⁺ doping / NCM622 / cycling stability / rate performance