Intrinsic Highly Conductive and Mechanically Robust Li‐Rich Cathode Materials Enabled by Microstructure Engineering for Enhanced Electrochemical Properties

• Published in: Advanced functional materials 2024-02, Vol.34 (6), p.n/a
• Main Authors: Liu, Yuanyuan, Zhang, Chenying, Lin, Liang, Ai, Xin, Gui, Siwei, Guo, Weibin, Li, Saichao, Wang, Laisen, Yang, Hui, Peng, Dong‐Liang, Xie, Qingshui
• Format: Article
• Language: English
• Subjects: Cathodes; Electrochemical analysis; Electrode materials; Ion transport; Lithium-ion batteries; Li‐rich Mn‐based layered cathode; microstructural engineering; Microstructure; Nanorods; Reaction kinetics; Robustness; Self-assembly; Spherical shells; stress regulation; Texturing; ultralong life; Voltage stability
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202308494

Li‐rich Mn‐based layered oxides (LRLO) are considered promising cathode candidates for high‐energy‐density lithium‐ion batteries (LIBs). However, severe capacity/voltage fading and poor rate performance hinder their practical application. Herein, a microstructure engineering strategy is put forward to design the unique bayberry‐like Li1.2Mn0.54Co0.13Ni0.13O2 (LRLO‐S) cathode material, composed of a spherical core and the shell self‐assembled by radially oriented nanorods with intrinsic rapid electron and ion transport capability, benefiting to increase the electrochemical reaction kinetics during cycling. Meanwhile, the radial texturing of the nanorods in shell layer forms a natural protective interface constituted by thermodynamically stable (003) planes, resisting electrolyte corrosion effectively. Furthermore, the configuration of orderly self‐assembled nanorods can effectively regulate the stress and strain to stabilize the lattice framework, finally improves the cycling stability of LRLO. As a result, the elaborately designed LRLO‐S cathode delivers remarkable high‐rate long‐term cycling stability with high capacity retentions of 91.2% after 500 cycles at 1 C and of 81.3% after 1000 cycles at 5 C. More importantly, the voltage stability is enhanced greatly with a superior retention of 89.6% after cycling 500 times at 1 C. Here a valuable strategy is provided to develop intrinsic mechanically robust high‐performance Li‐rich‐layered cathode materials for advanced LIBs. Li‐rich layered oxide cathode material Li1.2Mn0.54Ni0.13Co0.13O2 assembled by the radially oriented nanorods is successfully produced. The order radially orientation of nanorods can greatly improve the intrinsic structural stability and electronic and ionic conductivities. In addition, the exposed stable (003) plane can suppress the interfacial side reactions greatly. As a result, the designed bayberry‐like Li‐rich cathode shows greatly enhanced electrochemical performance.