Alleviating the Kinetic Hindrance of Ni-Rich Single-Crystal Cathode Materials Driven by Local Structural Realignment

作者：Zhengwei Xu, Zhixing Wang, Wu Meng, Bianzheng You, Xinxin Tan, Wei Yin, Mingxue Tang, Jie Liu, Maxim Avdeev, Wang Hay Kan, Huajun Guo, Wenjie Peng, Xinhai Li, Guangchao Li, Hui Duan, Jiexi Wang, Guochun Yan · 发表于：ACS Nano · 年份：2025 · DOI：10.1021/acsnano.5c06069 · 被引用次数：8 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Supercapacitor Materials and Fabrication

Crack-free Ni-rich single-crystal cathodes exhibit exceptional stability; however, they encounter challenges pertaining to kinetic hindrance, low capacity, and low initial Coulombic efficiency. Herein, we present a melt infiltration-dispersion method for synthesizing a small-sized single-crystal LiNi 0.90 Co 0.06 Mn 0.04 O 2 (N90-SC) material at lower temperatures, enabling kilogram-scale production. The inclusion of low-melting LiOH-Li 2 SO 4 eutectic salt enhances uniform mass and heat transfer while penetrating the grain boundaries of secondary particles, thereby inhibiting particle growth and resulting in small single crystals after washing. The elevated lithium potential effectively minimizes Li + /Ni 2+ disorder and facilitates the doping of a small amount of Li ions into the transition metal layers. Under a high state of charge, Ni ions migrate and occupy the lithium layer, resulting in the formation of a localized superlattice structure. This dynamic superlattice exerts a stabilizing pillar effect through robust Ni interlayer superexchange interactions, thus reinforcing the deintercalated structure and promoting a reversible H2–H3 phase transition. At the end of discharge, lithium doping reduces the lithium diffusion barrier by mitigating the electrostatic repulsion effect, enhancing the lithium diffusion coefficient and alleviating the kinetic hindrance of Ni-rich single-crystal cathodes. Consequently, the N90-SC material achieves a high capacity of 227.7 mAh g –1 an...