Suppressing the high-voltage phase transition in O3-type layered cathode enables ultra-stable sodium-ion batteries

作者：M. K. Yu, Ming Ma, Lina Yang, Qingling Guo, Shanshan Ye, Nazir Ahmad, Zixuan Jiang, Jiacheng Liang, Jing Xia, Bo Peng, Wenxiu He, Liang Shi, Genqiang Zhang · 发表于：Energy storage materials · 年份：2025 · DOI：10.1016/j.ensm.2025.104679 · 被引用次数：6 · 研究领域：Advancements in Battery Materials、Advanced Battery Materials and Technologies、Advanced Battery Technologies Research

O3-type transition metal layer oxide cathode materials are promising candidates for sodium-ion batteries, owing to their high theoretical capacity and ample sodium availability. However, they are challenged for operating at higher voltage (≥4.2 V) to realize high use of capacity with long cyclability, limited by the phase transition at high voltage. Herein, we show that the high-voltage phase transition of typical O3-NaFe 0.5 Mn 0.5 O 2 cathode can be well suppressed, by means of high entropy design strategy. As proof of concept, the designed low-cost O3-Na 0.8 Ni 0.2 Fe 0.25 Al 0.05 Mg 0.05 Ti 0.05 Mn 0.4 O 2 (HE-NFMO) cathode material exhibits suppressed high-voltage phase transition, which displays excellent electrochemical properties operated at high-voltage of 4.2 V. Consequently, the HE-NFMO cathode achieves a high capacity of 131.9 mAh g −1 at 0.1 C and long cycling life over 900 cycles at 5.0 C. Advanced characterizations combined with theoretical calculations confirm that the HE-NFMO could maintain a stable structural framework and show low Na + diffusion barrier, which demonstrate suppressed phase transition with ultra-low strain and fast Na + transfer kinetics. This study offers valuable insights for the design of ultra-stable cathode operated at high cut-off voltage.