Modulating Surface Architecture and Electronic Conductivity of Li‐rich Manganese‐Based Cathode

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-11, Vol.20 (44), p.e2400641-n/a
• Main Authors: Li, Zhi, Cao, Shuang, Chen, Jiarui, Wu, Lei, Chen, Manfang, Ding, Hao, Wang, Ruijuan, Guo, Wei, Bai, Yansong, Liu, Min, Wang, Xianyou
• Format: Article
• Language: English
• Subjects: Cathodes; Electrochemical analysis; electronic conductivity; F‐doped carbon; Interface stability; Lithium-ion batteries; Lithium‐rich manganese‐based materials; Manganese; Oxygen; Polyvinylidene fluorides; structure stability; surface reconstruction; Thermal stability
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202400641

Li‐rich manganese‐based cathode (LRMC) has attracted intense attention to developing advanced lithium‐ion batteries with high energy density. However, LRMC is still plagued by poor cyclic stability, undesired rate capacity, and irreversible oxygen release. To address these issues, herein, a feasible polyvinylidene fluoride (PVDF)‐assisted interface modification strategy is proposed for modulating the surface architecture and electronic conductivity of LRMC by intruding the F‐doped carbon coating, spinel structure, and oxygen vacancy on the LRMC, which can greatly enhance the cyclic stability and rate capacity, and restrain the oxygen release for LRMC. As a result, the modified material delivers satisfactory cyclic performance with a capacity retention of 90.22% after 200 cycles at 1 C, an enhanced rate capacity of 153.58 mAh g−1 at 5 C and 126.32 mAh g−1 at 10 C, and an elevated initial Coulombic efficiency of 85.63%. Moreover, the thermal stability, electronic conductivity, and structure stability of LRMC are also significantly improved by the PVDF‐assisted interface modification strategy. Therefore, the strategy of simultaneously modulating the surface architecture and the electronic conductivity of LRMC provides a valuable idea to improve the comprehensive electrochemical performance of LRMC, which offers a promising reference for designing LRMC with high electrochemical performance. A unique surface architecture with F‐doped carbon coating, spinel heterostructure, and oxygen vacancy is built on the Li‐rich manganese‐based cathode (LRMC) by a facile PVDF‐assisted interface modification strategy. Thanks to this surface architecture, the electronic conductivity, structure stability, and Li+ diffusion rate of LRMC are improved, thus enhancing the cyclic stability and rate capacity of LRMC.