Encapsulation of NMC811 with Multifunctional Materials for Next-Generation Li-Ion Batteries

Abstract

Ni-rich layered transition metal oxide is a promising cathode candidate for lithium-ion batteries owing to their superior advantages, e.g., high energy density, low cost, and eco-friendly. Nevertheless, the capacity fading usually occurs for high Ni content cathode. Herein, we introduce surface modification of Ni-rich cathode by the mechanofusion process that can enhance electrochemical capacity and cycling stability, especially for 18650 cells. The multifunctional shell includes a number of materials for enhancing the electrical conductivty, ionic conductivity, and chemical and mechanical stabilities. No change in the structure of the coated Ni-rich cathode is observed and the coating material has completely covered the surface with a thickness of 100 nm after the mechanofusion process. As an electrochemical result, the coated cathode shows outstanding performance with high-capacity retention in comparison to the uncoated cathode due to coating materials can prevent direct contact between the electrolyte and the cathode and enhance ionic conductivity.