中国石油大学（华东）邢伟团队探明了非磁性硅梯度渗透减轻无钴富镍阴极的动力学滞后。相关研究成果发表在2024年9月2日出版的《德国应用化学》。

无钴富镍层状氧化物因其成本效益和高容量而被认为是下一代锂离子电池的有前景的阴极材料。然而，由于锂离子扩散动力学的滞后，它们仍然面临着低放电容量和低倍率性能的实际挑战。

该文中，基于晶格磁挫折的调节，研究人员通过掺杂非磁性Si元素，从根本上解决了作为动力学磁滞主要来源的Li/Ni混合缺陷。同时，通过采用梯度渗透掺杂，在无钴富镍阴极上构建了具有可逆晶格析氧和低晶格应变的稳健Si-O表面结构，以抑制表面致密势垒层的形成。

随着原子和电极颗粒尺度上锂离子扩散动力学的显著增强，所获得的阴极（LiNi_xMn_1-xSi_0.01O₂，0.6≤x≤0.9）在放电容量、倍率能力和耐久性方面具有优异的性能。

该项工作强调了磁结构和界面化学物质对锂离子输运性质的耦合效应，这一概念将激励更多的研究人员进行深入的研究。

附：英文原文

Title: Mitigating the Kinetic Hysteresis of Co-free Ni-rich Cathodes via Gradient Penetration of Nonmagnetic Silicon

Author: Yijun Song, Yongpeng Cui, Bo Wang, Lina Ge, Li Zhou, Zhijian Qiu, Zhipeng Xie, Debin Kong, Xiaofang Li, Jianqiang Zhang, Lei Zhu, Pengyun Liu, Xuejin Li, Zifeng Yan, Qingzhong Xue, Yongfu Tang, Wei Xing

Issue&Volume: 2024-09-02

Abstract: Co-free Ni-rich layered oxides are considered a promising cathode material for next-generation Li-ion batteries due to their cost-effectiveness and high capacity. However, they still suffer from the practical challenges of low discharge capacity and poor rate capability due to the hysteresis of Li-ion diffusion kinetics. Herein, based on the regulation of the lattice magnetic frustration, the Li/Ni intermixing defects as the primary origin of kinetic hysteresis are radically addressed via the doping of the nonmagnetic Si element. Meanwhile, by adopting gradient penetration doping, a robust Si-O surface structure with reversible lattice oxygen evolution and low lattice strain is constructed on Co-free Ni-rich cathodes to suppress the formation of surface dense  barrier layer. With the remarkably enhanced Li-ion diffusion kinetics in atomic and electrode particle scales, the as-obtained cathodes (LiNixMn1-xSi0.01O2, 0.6 ≤ x ≤ 0.9) achieve superior performance in discharge capacity, rate capability, and durability. This work highlights the coupling effect of magnetic structure and interfacial chemicals on Li-ion transport properties, and the concept will inspire more researchers to conduct an intensive study.

DOI: 10.1002/anie.202409764

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202409764