北京理工大学陈来团队报道了，稀土掺杂增强富镍锂离子电池阴极化学机械稳定性的钉扎效应。相关研究成果发表在2025年1月23日出版的国际学术期刊《中国化学》。

富镍层状三元阴极材料（NCM）因其高比容量和低成本而得到了广泛的研究。然而，随着镍含量的增加，NCM材料的不稳定结构逐渐变得突出。循环前表面残留碱和Li⁺/Ni²⁺混合、相变、过渡金属离子溶解、微裂纹等问题是富镍材料容量快速衰减的主要原因。

该文中，Sc³⁺被掺杂到LiNi_0.8Co_0.1Mn_0.1O₂材料中，这已被证明会阻碍Li⁺/Ni²⁺的混合，同时增加层间距。这导致材料结构的稳定以及循环稳定性和速率性能的增强。值得注意的是，单粒子力测试和高角度环形暗场扫描透射电子显微镜（HAADF-STEM）成像进一步表明，应力累积减少，化学机械故障减轻。

该项研究强调了少量添加多功能稀土掺杂，在增强富镍阴极的化学机械稳定性方面的功效，为优化储能阴极的设计和性能提供了一种简单而全面的解决方案。

附：英文原文

Title: Rare-Earth Doping Induced Pinning Effect with Enhanced Chemo-Mechanical Stability in Ni-Rich Cathodes for Lithium-Ion Batteries

Author: Bin Zhang, Hongyun Zhang, Yuefeng Su, Jinyang Dong, Kang Yan, Jinzhong Liu, Yun Lu, Haoyu Wang, Chengzhi Wang, Feng Wu, Lai Chen

Issue&Volume: 2025-01-23

Abstract: The nickel-rich layered ternary cathode material (NCM) has been extensively studied due to its high specific capacity and low cost. Nevertheless, with the increase of Ni content, the unstable structure of NCM material has gradually become prominent. Residual alkali on the surface and Li+/Ni2+ mixing before cycling, phase change, transition metal ions dissolution, microcracking, and other issues during the cycle, are the primary causes for the fast capacity fading of Ni-rich materials. In this study, Sc3+ is doped into the LiNi0.8Co0.1Mn0.1O2 material, which has been demonstrated to impede the Li+/Ni2+ mixing, while simultaneously increasing the layer spacing. This results in the stabilization of the material structure and an enhancement of both the cycling stability and the rate performance. Notably, single-particle force testing and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging further demonstrate reduced stress accumulation and mitigated chemo-mechanical failure. This study underscores the efficacy of a minor addition of multifunctional rare-earth doping in enhancing the chemo-mechanical stability of Ni-rich cathodes, offering a straightforward and comprehensive solution to optimize the design and performance of energy storage cathodes.

DOI: 10.1002/cjoc.202401071

Source: https://onlinelibrary.wiley.com/doi/full/10.1002/cjoc.202401071