Preparation and electrochemical investigation of single-crystal LiNi0.6Co0.2Mn0.2O2 for high-performance lithium-ion batteries

Ni-rich layered cathode materials have large reversible capacity. However, they suffer from the cracking of the spherical particles, low Coulombic efficiency and fast capacity decay during cycling. Preparing a single-crystal Ni-rich cathode is a promising method to solve this problem due to its excellent structural stability. However, the morphology and electrochemical performance of single-crystal Ni-rich cathodes depend largely on the particle size and morphology of the hydroxide precursors. In this work, a suitable hydroxide precursor to synthesise single-crystal NCM622 with great dispersity and remarkable electrochemical performance is explored. Besides, the influence of grain size on the structural and thermal stability of the Ni-rich cathode material is further investigated. This work provides a reference to synthesize single-crystal Ni-rich cathodes with high electrochemical performance for lithium-ion batteries of the next generation.