储能科学与技术

• 储能科学与技术 •    

富镍三元正极材料的失效机理及改性策略

黄小荣1(), 刘健达1, 芦大伟1, 易斌2, 徐云1, 秦啸天2   

  1. 1.广东电网有限责任公司东莞供电局,广东 东莞 523000
    2.广东新型储能国家研究院有限 公司,广东 广州 510000
  • 收稿日期:2025-08-08 修回日期:2025-09-18
  • 通讯作者: 黄小荣 E-mail:706360854@qq.com
  • 作者简介:黄小荣(1985—),男,硕士研究生,高级工程师,研究方向为储能与低压直流,E-mail:706360854@qq.com
  • 基金资助:
    南方电网科技项目(031900KC24040028)

The failure mechanisms of nickel-rich ternary cathode materials and modification strategies

Xiaorong HUANG1(), Jianda LIU1, Dawei LU1, Bin YI2, Yun XU1, Xiaotian QIN2   

  1. 1.Dongguan Power Supply Bureau of Guangdong Power Grid Corporation, Dongguan 523000, Guangdong, China
    2.National Institute of Guangdong Advanced Energy Storage, Guangzhou 510000, Guangdong, China
  • Received:2025-08-08 Revised:2025-09-18
  • Contact: Xiaorong HUANG E-mail:706360854@qq.com

摘要:

富镍三元正极材料(NCM/NCA)因其兼具高能量密度与优异倍率性能,在电动汽车与储能领域受到广泛应用。随着镍含量的提升,材料可逆比容量显著提高,但高镍化同时引发材料结构与化学稳定性下降,导致电池循环寿命缩短,并增大安全隐患。本文系统梳理了富镍三元正极材料的主要失效机理,并分析其对电池性能的影响规律。其中,Li+/Ni2+阳离子混排引起部分锂离子位点失活,降低材料可逆容量;材料高活性表面导致其在存储及充放电循环中易发生表面/界面副反应,加速材料表面不可逆相变及电解液分解;同时,正极颗粒在连续充放电过程中因各向异性应力积累而产生微裂纹,导致结构坍塌,并增加电解液与正极的接触面积,加剧界面副反应。针对上述问题,近年来提出了多种改性策略,包括构建氧化物或有机物涂层以提升界面稳定性,元素掺杂以优化结构稳定性和离子扩散动力学,浓度梯度设计以兼顾高比容量与界面稳定性,以及单晶化以缓解颗粒裂纹和界面副反应。最后,本文对富镍三元正极材料未来的研究方向进行展望,为下一代高能量密度锂离子电池研究提供参考。

关键词: 锂离子电池, 富镍三元正极, 失效机理, 改性策略

Abstract:

Nickel-rich layered oxide cathodes (NCM/NCA) have been widely applied in electric vehicles and energy storage systems owing to their combination of high energy density and excellent rate capability. With increasing nickel content, the reversible capacity of the material is significantly enhanced. however, high nickel content simultaneously leads to reduced structural and chemical stability, thereby reducing the cycle life of the battery and exacerbating safety concerns. This review systematically summarizes the major degradation mechanisms of nickel-rich layered oxide cathodes and elucidates their impact on electrochemical performance. Specifically, Li+/Ni2+ cation mixing results in the deactivation of lithium-ion sites and a reduction in reversible capacity. The high surface reactivity of these materials makes them prone to surface and interfacial reactions during storage and cycling, which accelerates irreversible phase transitions and electrolyte decomposition. Furthermore, the accumulation of anisotropic stress during repeated cycling induces microcrack formation within cathode particles, ultimately causing structural collapse and increasing the electrode–electrolyte contact area, which further aggravates interfacial reactions. To address these issues, diverse modification strategies have been proposed in recent years, including surface coatings with oxides or organics to enhance interfacial stability, elemental doping to improve structural stability and ion diffusion kinetics, concentration-gradient designs to achieve high capacity and interfacial stability, and single-crystal engineering to mitigate particle cracking and interfacial reactions. Finally, the future research directions of nickel-rich cathode materials are discussed, providing insights for the development of next-generation high-energy density lithium-ion batteries.

Key words: lithium-ion battery, nickel-rich ternary cathode, failure mechanism, modification strategy

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