posted on 2022-02-07, 16:03authored byShouyi Yin, Hongyi Chen, Jun Chen, Abouzar Massoudi, Wentao Deng, Xu Gao, Shu Zhang, Ying Wang, Tsung-Wu Lin, Craig E. Banks, Shi-zhang Qiao, Guoqiang Zou, Hongshuai Hou, Xiaobo Ji
The
implementation of Ni-rich cathodes with high energy density
has been critically restrained by stress corrosion. Herein, crack-free
LiNbO3-coated LiNi0.88Co0.10Mn0.02O2, as theoretically predicted, demonstrates
highly reversible lithiation/delithiation. Mechanically, the phase
transition (H1 → H2 → H3) is significantly alleviated
by the excogitation of the interfacial force invoked by the LiNbO3 coating layer, as verified by X-ray absorption spectroscopy
and extended X-ray absorption near-edge structure spectroscopy. Meanwhile,
the stabilities of the crystal structure are remarkably strengthened
by the strong Nb–O bond activated by Nb5+ doping
that is confirmed by Rietveld refinement of X-ray diffraction and
differential capacitance curves. Chemically, the interface shielding
effect is conducive to protecting the electrode against electrolyte
corrosion along with subsequent transition-metal dissolution, ultimately
rendering a faster/highly convertible lithium-ion diffusion. Greatly,
the excellent electrochemical properties (74% capacity retention after
300 cycles at 2 C within 2.5–4.3 V) and structural stability
(the morphology remains intact after 500 cycles at 5 C within 2.5–4.3
V) are successfully achieved. Given this, this elaborate work might
inaugurate a potential avenue for rationally tuning the structure/interface
evolution toward Ni-rich materials.