1. Structural insights into composition design of Li-rich layered cathode materials for high-energy rechargeable battery.
- Author
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Yin, Chong, Wei, Zhining, Zhang, Minghao, Qiu, Bao, Zhou, Yuhuan, Xiao, Yinguo, Zhou, Dong, Yun, Liang, Li, Cheng, Gu, Qingwen, Wen, Wen, Li, Xiao, Wen, Xiaohui, Shi, Zhepu, He, Lunhua, Shirley Meng, Ying, and Liu, Zhaoping
- Subjects
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STORAGE batteries , *CATHODES , *LITHIUM cell electrodes , *ENERGY density , *ELECTRONIC structure , *OXIDATION-reduction reaction , *OXYGEN - Abstract
[Display omitted] The Li-rich layered oxide is considered as one of the most promising cathode materials for high energy density batteries, due to its ultrahigh capacity derived from oxygen redox. Although incorporating over-stoichiometric Li into layered structure can generate Li 2 MnO 3 -like domain and enhance the oxygen redox activity thermodynamically, the fast and complete activation of the Li 2 MnO 3 -like domain remains challenging. Herein, we performed a systematic study on structural characteristics of Li-rich cathode materials to decipher the factors accounting for activation of oxygen redox. We reveal that the activation of Li-rich cathode materials is susceptible to local Co coordination environments. The Co ions can intrude into Li 2 MnO 3 -like domain and modulate the electronic structure, thereby facilitating the activation of Li-rich layered cathode materials upon first charging, leading to higher reversible capacity. In contrast, Li 2 MnO 3 -like domain hardly contains any Ni ions which contribute little to the activation process. The optimum composition design of this class of materials is discussed and we demonstrate a small amount of Co/Mn exchange in Li 2 MnO 3 -like domain can significantly promote the oxygen redox activation. Our findings highlight the vital role of Co ions in the activation of oxygen redox Li-rich layered cathode materials and provide new insights into the pathway toward achieving high-capacity Li-rich layered cathode materials. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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