In situ formed partially disordered phases as earth-abundant Mn-rich cathode materials

作者：Zijian Cai, Bin Ouyang, H. Hau, Tina Chen, R. Giovine, K. Koirala, Linze Li, Huiwen Ji, Yang Ha, Yingzhi Sun, Jianping Huang, Yu Chen, Vincent C. Wu, Wanli Yang, Chongmin Wang, R. Clément, Zhengyan Lun, G. Ceder · 发表于：Nature Energy · 年份：2023 · DOI：10.1038/s41560-023-01375-9 · 被引用次数：115

Earth-abundant cathode materials are urgently needed to enable scaling of the Li-ion industry to multiply terawatt hours of annual production, necessitating reconsideration of how good cathode materials can be obtained. Irreversible transition metal migration and phase transformations in Li-ion cathodes are typically believed to be detrimental because they may trigger voltage hysteresis, poor kinetics and capacity degradation. Here we challenge this conventional consensus by reporting an unusual phase transformation from disordered Li- and Mn-rich rock salts to a new phase (named δ ), which displays partial spinel-like ordering with short coherence length and exhibits high energy density and rate capability. Unlike other Mn-based cathodes, the δ phase exhibits almost no voltage fade upon cycling. We identify the driving force and kinetics of this in situ cathode formation and establish design guidelines for Li- and Mn-rich compositions that combine high energy density, high rate capability and good cyclability, thereby enabling Mn-based energy storage. Earth-abundant, inexpensive cathode materials are highly desirable for the sustainable development of batteries. Here the researchers report that a manganese-rich, cation-disordered rock salt material exhibits—via an in situ phase transition to a partially disordered spinel phase during cycling—potentially high energy density and rate capability.