（1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083,
China; 2. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing,
Beijing100083, China; 3. Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious
Metals, University of Science and Technology Beijing, Beijing100083, China）
Abstract：Ni-rich cathode is one of the key materials to promote the development of lithium-ion battery technol‐
ogy due to its high specific energy and long cycle life. The grain morphology of traditional Ni-rich cathodes is
polycrystalline spherical particles. Crack is easy to be formed in the polycrystalline spherical particles during the
electrochemical cycle, which contributes to the deterioration of electrochemical performance and the battery safe‐
ty problems. The single crystallization strategy can improve effectively the long-term cycle performance and
safety of Ni-rich cathodes, and alleviate the problems of thermal stability, crystal structure and particle structure
stability of Ni-rich cathodes. However, the slow kinetics of lithium-ion diffusion presents a significant challenge
for single-crystalline Ni-rich cathodes, as it can lead to the deterioration of rate performance and a decline in material structure. In this paper, the differences in structure and electrochemical properties between single-crystal‐
line cathodes and traditional polycrystalline cathodes are compared, the stability mechanism of single-crystalline
cathodes is analyzed, the effect of slow lithium-ion diffusion kinetics on their deterioration mechanism is empha‐
sized, and the current strategies to improve the lithium-ion diffusion kinetics of single-crystalline Ni-rich cath‐
odes are summarized. Finally, we propose the future research focus on improving the lithium-ion diffusion dy‐
namics of single-crystalline Ni-rich cathodes, providing theoretical guidance for their industrialization.
2023, Vol. 33 
