Solid-state approach for synthesizing single crystal LiNi_0.8Co_0.1Mn_0.1O₂ cathode of lithium-ion batteries

Single crystal Ni-rich LiNi_xCo_yMn_1−x-yO₂ (SC-NCM) cathode has been highly concerned for increased cyclic stability and safety. However, the ideal approach for synthesizing SC-NCM is still challenging. In this work, single crystal LiNi_0.8Co_0.1Mn_0.1O₂ (SC-NCM811) cathode with a well-layered structure was successfully synthesized by a simple and contamination-free solid-state approach. The results showed that higher calcination temperature (above 900 ℃) resulted in a rapid increase in particle size, which caused low discharge capacity due to the prolonged lithium diffusion pathway. Under the oxygen atmosphere, SC-NCM811 exhibited improved capacity retention compared to the air atmosphere, which could be attributed to the increased lattice oxygen content and reduced Li/Ni mixing. The prepared SC-NCM811 delivered an initial discharge capacity of 191mAh g⁻¹ and showed 74% capacity retention after 100 cycles. The present work provides a simple and contamination-free approach for synthesizing single crystal Ni-rich cathode.