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Introducing electrolytic electrochemical polymerization for constructing protective layers on Ni-rich cathodes of Li-ion batteries

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Abstract

LiNi0.8Co0.1Mn0.1O2 (NCM811) is the most promising cathode for high-energy Li-ion batteries, despite its poor cycling stability that originates from the reactions that occur with the electrolyte. Herein, to solve this interfacial issue, a facile electrolytic electrochemical polymerization process was introduced in this paper, and a uniform conductive electrolyte interface (polyaniline) was successfully constructed on the surface of the NCM811 porous electrode (PANI-NCM), which facilitated the charge transfer during charge/discharge. The side reactions at the interface between the cathode and the electrolyte are suppressed, and thereby, the cycling performance and rate capability are considerably improved. PANI-NCM delivers an initial capacity of 157.2 mAh·g−1 as well as excellent cyclability (capacity retention of 88% after 500 cycles at 2C), whereas the capacity of the bare NCM811 has dropped to 31.3 mAh·g−1. In addition, polypyrrole and polythiophene also can be formed through electrolytic electrochemical polymerization process, which provides a practicable tactic to modify the interfacial stability of cathodes for high-energy Li-ion batteries.

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摘要

LiNi0.8Co0.1Mn0.1O2 (NCM811) 作为高能锂离子电池最有前途的正极材料, 其由于与电解质发生反应而导致循环稳定性较差。 为了解决这个界面问题, 本文引入了一种简便的电解电化学聚合方法, 在NCM811多孔电极表面成功构建了均匀的导电电解质界面 (聚苯胺) (PANI-NCM), 促进充电/放电期间传输, 抑制了正极与电解质界面的副反应, 从而显着提高了循环性能和倍率性能。PANI-NCM 电极表现出157.2 mAh·g−1 的初始容量以及良好的循环性能 (2 C 下 500 次循环后容量保持率为 88%), 而 NCM811电极500次后容量降至 31.3 mAh·g−1。此外, 还可以通过电解电化学聚合过程形成聚吡咯和聚噻吩, 该方法为改善高能锂离子电池正极的界面稳定性提供了可行的策略。

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Acknowledgements

This study was financially supported by the National Natural Science Foundation of China (Nos. 52172227 and Z190010).

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  1. Lin-Tao Dou and Bei Li have contributed equally to this work.

Authors and Affiliations

  1. School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, 430205, China

    Lin-Tao Dou, Bei Li, Hao-Long Nie, Chao-Qun Shang, Xiao-Min Wang, Zhan-Hui Zhang & Pu Hu

  2. Huairou Division, Institute of Physics, Chinese Academy of Sciences, Beijing, 101400, China

    Dong-Dong Xiao

  3. Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, 32603, USA

    Katerina E. Aifantis

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Dou, LT., Li, B., Nie, HL. et al. Introducing electrolytic electrochemical polymerization for constructing protective layers on Ni-rich cathodes of Li-ion batteries. Rare Met. 43, 2536–2545 (2024). https://doi.org/10.1007/s12598-024-02651-7

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