Highly Dispersed Micrometer Nickel-Rich Single-Crystal Construction: Benefits of Supercritical Reconstruction during Hydrothermal Synthesis
Yong Li, Jingjing He, Liang Luo, Xuebao Li, Zewei Chen, Yibo Zhang, Yibo Zhang, Lunhao Deng, Peng Dong, Shunyi Yang, Kaipeng Wu, Ding Wang, Yingjie Zhang, Yingjie Zhang, Jianguo Duan
Abstract
The disordered volume effect of anisotropic primary particles during electrochemical processes is a key problem in the electrochemical instability of LiNiO2-based cathode materials. In this work, Ni0.8Co0.1Mn0.1(OH)2 precursors with a hexagonal morphology were synthesized via a hydrothermal method. Highly crystalline micrometer Ni-rich single-crystal LiNi0.8Co0.1Mn0.1O2 cathode materials with excellent dispersion were successfully prepared at a relatively lower calcination temperature and excess lithium ratio than those of conventional methods. When compared to traditional commercial Ni-rich polycrystalline cathodes, these single-crystal cathode materials had a better initial capacity of 186.2 mAh g–1 and an excellent capacity retention of ∼93.4% (2.8–4.3 V) after 100 cycles at 1 C. Moreover, monodispersed, micrometer- and submicrometer-sized Li-storage architectures shortened the Li+-diffusion distance and provided upgraded rate performance, achieving a capacity of 130.4 mAh g–1 at a rate of 10 C. Thus, the hydrothermal construction of a single-crystal precursor-assisted mild sintering strategy was effective for designing single-crystal Ni-rich Li-storage structures with good electrochemical properties.