Direct Synthesis of Single-Crystalline LiNi0.8Co0.1Mn0.1O2 Cathodes From Lithium-Containing Precursors via Spray Pyrolysis.

Single-crystalline cathode materials have attracted considerable attention for addressing the cycling instability of Ni-rich layered cathode materials caused by anisotropic lattice strain during repeated cycling. However, conventional synthesis methods for single-crystalline cathodes generally require high temperatures and prolonged calcination times. Alternative approaches, such as multistep lithiation, molten-salt, and hydrothermal methods, still suffer from limitations such as complex processes, mandatory washing, and challenges in large-scale production. Therefore, in this study, a direct synthesis strategy for single-crystalline LiNi0.8Co0.1Mn0.1O2 (SC-NCM) cathode materials was proposed using Li-containing precursors prepared by spray pyrolysis. Because lithium was homogeneously incorporated within the precursor particles, SC-NCM was successfully synthesized through direct calcination without additional Li-mixing or washing processes. As a result, single-crystalline NCM was successfully crystallized at 900 °C for 3 h with 700 °C for 6 h healing sequence and exhibited superior cycling performance compared with polycrystalline NCM (PC-NCM), delivering a capacity retention of 81% after 1000 cycles at 0.5 C. Therefore, this work provides an effective approach to simultaneously address both the intrinsic limitations of Ni-rich layered cathode materials and the challenges associated with conventional synthesis processes.