Liang Xinghui, Song Xiaosheng, Sun H Hohyun, Kim Hun, Kim Myoung-Chan, Sun Yang-Kook
Department of Energy Engineering, Hanyang University, Seoul, South Korea.
Department of Chemical and Biological Engineering, University of Alabama, Tuscaloosa, Alabama, USA.
Nat Commun. 2025 Apr 13;16(1):3505. doi: 10.1038/s41467-025-58637-1.
O3-type layered oxide for sodium-ion batteries have attracted significant attention owing to their low cost and high energy density. However, their applications are restricted by rapid capacity decay during long-term cycling, with uneven Na distribution and microcrack formation being key contributing factors. In this study, a customized reconstruction layer integrating a fast ion conductor NaCaPO coating with gradient Ca doping is developed to enhance the surface chemical and mechanical stability of the layered cathodes. The gradient Ca doped interphase facilitates uniform phase transformation within the particles, minimizes lattice mismatch, ensures even Na distribution, and mitigates microcrack formation through a pinning effect. Consequently, the optimized sample exhibits improved electrochemical performance and robust reliability under high-voltage conditions and a broad temperature range (-10 to 50 °C). The practical feasibility of a pouch-type full cell paired with a hard carbon anode is demonstrated by a high capacity retention of 82.9% after 300 cycles at 0.5 C. This scalable interface modification strategy provides valuable insights into the development of advanced oxide cathode materials for sodium-ion batteries.
用于钠离子电池的O3型层状氧化物因其低成本和高能量密度而备受关注。然而，它们的应用受到长期循环过程中容量快速衰减的限制，钠分布不均和微裂纹形成是关键因素。在本研究中，开发了一种定制的重构层，该重构层集成了具有梯度钙掺杂的快速离子导体NaCaPO涂层，以增强层状阴极的表面化学和机械稳定性。梯度钙掺杂的界面相促进颗粒内部的均匀相变，最小化晶格失配，确保钠分布均匀，并通过钉扎效应减轻微裂纹形成。因此，优化后的样品在高压条件和较宽温度范围（-10至50°C）下表现出改善的电化学性能和强大的可靠性。通过在0.5C下300次循环后82.9%的高容量保持率，证明了与硬碳阳极配对的软包型全电池的实际可行性。这种可扩展的界面改性策略为钠离子电池先进氧化物阴极材料的开发提供了有价值的见解。
