Ce-modified LiNi0.5Co0.2Mn0.3O2 cathode with enhanced surface and structural stability for Li ion batteries

• Published in: Advanced powder technology : the international journal of the Society of Powder Technology, Japan Vol. 32; no. 7; pp. 2493 - 2501
• Main Authors: Yi, Hongling, Tan, Lei, Xia, Lingfeng, Li, Lingjun, Li, Hongxing, Liu, Zengsheng, Wang, Chu, Zhao, Zixiang, Duan, Junfei, Chen, Zhaoyong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2021
• Subjects: Advanced Li-ion batteries; Capacity fade; Ce doping; CeO2 coating; Structural instability; Capacity fade; CeO2 coating; Advanced Li-ion batteries; Structural instability; Ce doping
• ISSN: 0921-8831; 1568-5527
• DOI: 10.1016/j.apt.2021.05.012

[Display omitted] •Ce-doped and CeO2-coated LiNi0.5Co0.2Mn0.3O2 cathode is synthesized via a simple route.•Ce-doping can reduce the degree of cation mixing by 0.5%.•The capacity retention of Ce-modified NCM cathode is increased by 9.6%.•The 2% Ce-modified sample shows the best Li+ diffusion coefficient. The well-established LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode materials possess a broad prospect for Li-ion batteries. However, the NCM523 still suffers severe capacity fading and structural instability. In this research, Ce-doped and CeO2-coated NCM523 cathode materials are synthesized by a smart one-step calcination process. It is found that the CeO2 coating layer is formed during high-temperature calcination. The CeO2 coating layers stop the electrode from being exposed to the electrolyte directly and promote the kinetics of lithium deintercalation. Besides, Ce doping could suppress the bulk cation-mixing degree. Electrochemical tests suggest that Ce-modification improves the capacity retention of cathode materials. The optimized Ce-modification cathode material, among 2.7 V and 4.6 V, not only shows the best capacity retention of 76.2%, but also delivers a discharge capacity of 178.2 mAh g−1 at 1 C. This smart modification strategy provides novel ideas for advanced LIBs.