Robust LiNi<sub>0.6</sub>Mn<sub>0.4</sub>O<sub>2</sub> Cathode Achieved from the Dual-Function Strategy of Microstructural Stress Dissipation and Crystalline Phase Ion Transport Improvement.

Li, Yuanyuan; Chen, Song; Zhang, Qiusheng; Zhang, Ye; Zhou, Zhiqun; Cui, Chunyu; Sun, Hongtao; Zhu, Jian et al. · ACS Nano · 2026

basic_science · Level V

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Abstract

LiNi<sub>0.6</sub>Mn<sub>0.4</sub>O<sub>2</sub> (NM64), a cobalt-free cathode material with high theoretical capacity and approximately 30% lower cost than commercial LiNi<sub>0.6</sub>Co<sub>0.2</sub>Mn<sub>0.2</sub>O<sub>2</sub> (NCM622), is a promising cathode for lithium-ion batteries. However, structural instability and sluggish kinetics limit its potential for large-scale commercial applications. To address these challenges, we propose a dual-function strategy that simultaneously enhances ion transport by reducing cation mixing and dissipates stress via elongated primary grains in oxygen-calcined NM64 (O-NM64), achieving superior robustness. Consequently, the O-NM64 exhibits a high specific capacity of 201.6 mAh g<sup>-1</sup> at 0.2 C, coupled with a high-rate capability of 153.40 mAh g<sup>-1</sup> at 10 C and long-term cycling stability, as evidenced by an 81.38% capacity retention after 450 cycles at 0.2 C (more than 220 days of continuous operation). Moreover, a 20 kg-scale pouch cell shows no significant capacity degradation over 300 cycles. This work demonstrates an effective approach for developing high-energy, high-power, long-cycle, resource-saving, and low-cost cathodes, offering insights into sustainable battery technologies that balance performance and cost.