Imitating Architectural Mortise-Tenon Structure for Stable Ni-Rich Layered Cathodes.

Tan, Xinghua; Chen, Zhefeng; Liu, Tongchao; Zhang, Yongxin; Zhang, Mingjian; Li, Shunning; Chu, Weiguo; Liu, Kang et al. · Adv Mater · 2023

basic_science · Level V

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Abstract

Ni-rich layered oxides are the most promising cathodes for Li-ion batteries, but chemo-mechanical failures during cycling and large first-cycle capacity loss hinder their applications in high-energy batteries. Herein, by introducing spinel-like mortise-tenon structures into the layered phase of LiNi<sub>0.8</sub> Co<sub>0.1</sub> Mn<sub>0.1</sub> O<sub>2</sub> (NCM811), the adverse volume variations in cathode materials can be significantly suppressed. Meanwhile, these mortise-tenon structures play the role of the expressway for fast lithium-ion transport, which is substantiated by experiments and calculations. Moreover, the particles with mortise-tenon structures usually terminate with the most stable (003) facet. The new cathode exhibits a discharge capacity of 215 mAh g<sup>-1</sup> at 0.1 C with an initial Coulombic efficiency of 97.5%, and capacity retention of 82.2% after 1200 cycles at 1 C. This work offers a viable lattice engineering to address the stability and low initial Coulombic efficiency of the Ni-rich layered oxides, and facilitates the implementation of Li-ion batteries with high-energy density and long durability.