Boosting the electrochemical performance of Li-rich Mn-based cathode materials via oxygen vacancy and spinel phase integration

Wenhua Yu; Liuyang Zhao; Yanyan Wang; Chengyu Yang; Jie Wang; Hao Huang; Aimin Wu; Xufeng Dong; Guozhong Cao

doi:10.1016/j.jcis.2023.06.050

Boosting the electrochemical performance of Li-rich Mn-based cathode materials via oxygen vacancy and spinel phase integration

J Colloid Interface Sci. 2023 Oct 15:648:820-833. doi: 10.1016/j.jcis.2023.06.050. Epub 2023 Jun 10.

Authors

Wenhua Yu¹, Liuyang Zhao², Yanyan Wang², Chengyu Yang², Jie Wang², Hao Huang³, Aimin Wu², Xufeng Dong⁴, Guozhong Cao⁵

Affiliations

¹ Key Laboratory of Energy Materials and Devices (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, China; College of Energy Storage Technology, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China.
² Key Laboratory of Energy Materials and Devices (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, China.
³ Key Laboratory of Energy Materials and Devices (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, China. Electronic address: huanghao@dlut.edu.cn.
⁴ Key Laboratory of Energy Materials and Devices (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, Liaoning Province, China. Electronic address: dongxf@dlut.edu.cn.
⁵ Department of Materials and Engineering, University of Washington, Seattle, WA 98195-2120, USA.

PMID: 37327625
DOI: 10.1016/j.jcis.2023.06.050

Abstract

Li-rich Mn-based oxide cathodes (LMOs) are regarded as one of the most prospective high energy density cathodes due to the reversible anion redox reaction, which gives them a very high capacity. However, LMOs materials usually have problems like low initial coulombic efficiency (ICE) and poor cycling performance during cycling, which are associated with irreversible surface O₂ release and unfavourable electrode/electrolyte interface side reactions. Herein, an innovative and scalable NH₄Cl-assisted gas-solid interfacial reaction treatment technique is employed to construct oxygen vacancies and spinel/layered heterostructures simultaneously on the surface of LMOs. The synergistic effect of the oxygen vacancy and the surface spinel phase can not only effectively enhance the redox properties of the oxygen anion and inhibit irreversible oxygen release, but also effectively mitigate the side reactions at the electrode/electrolyte interface, inhibit the formation of CEI films and stabilize the layered structure. The electrochemical performance of the treated NC-10 sample improved significantly, showing an increase in ICE from 77.4 % to 94.3 % and excellent rate capability and cycling stability, with a capacity retention of 77.9 % after 400 cycles at 1 C. This oxygen vacancy and spinel phase integration strategy offers an exciting prospect and avenue for improving the integrated electrochemical performance of LMOs.

Keywords: Electrochemical performance; Initial Coulombic efficiency; Li-rich Mn-based cathode materials; Oxygen vacancies; Spinel phase.