Fabrication of Li-Rich Cathodes with Enhanced Stability and Electrochemical Performances for Lithium Ion Battery

Abstract

Li-ion batteries, an ultimate rechargeable energy storage, play more and more important roles in modern people's life and activity. Developing energy storage equipments with high specific energy and stability that can work at very high charge-discharge rate is crucial for efficient use of energy at power-hungry laptops, cameras, mobile phones and electric cars. From the perspective of chemistry, these can be achieved by raising voltage window, controlling the structure transition during charge/discharge proces, and significantly improving the kinetics of lithium ions and electrons in electrode. Here, we will address the our recental finding for enhancing stability and electrochemical performances of Li-rich cathode materials, especially on (1) an simple methode to resolve kinetics problems of ultrafast charging-discharging Li-ion batteries by fabrication of layered LiMO2 (M=Mn, Co, Ni) hexagonal sheet exposing with facets {101}, (2) in situ potassium doping to stabilize the host layered structure by prohibiting the formation of spinel structure during cycling, and (3) optimizing the interactions between the components Li2MnO3 and LiMO2 in the Li-rich oxide (i.e. stabilizing the layered structure through Li2MnO3 and controlling Li2MnO3 activation through LiMO2).