A MOF-Based Strategy for Synthesizing High-Strength Single-Crystal NCM811 Cathode Materials

Single-crystal ternary cathode materials are regarded as promising next-generation cathode materials for lithium-ion batteries due to their excellent cycling performance and high safety. However, the industrial-scale production of single-crystal NCM continues to pose significant challenges, primarily attributable to complex processing routes and high manufacturing costs. In this work, the electrochemical behavior of NCM cathodes is explored in relation to the varying temperatures at which metal–organic framework (MOF) precursors are prepared. The MOFs were synthesized using nickel–cobalt–manganese acetates and terephthalic acid as starting materials. The MOF-derived precursors exhibit high reactivity, enabling the synthesis of single-crystal NCM811 via conventional solid-state sintering. The results reveal that increasing the preparation temperature of the Ni/Co/Mn-based MOF precursor leads to a progressive increase in Li/Ni cation disorder within the resultant NCM cathode material. Among the samples, MOF-NCM-0, prepared at 0 °C and derived from Ni/Co/Mn-MOF precursors via sintering, exhibits the most favorable electrochemical performance. Compared with the commercial polycrystalline cathode material (PC-NCM), the single-crystal MOF-NCM-0 synthesized in this study demonstrates superior properties, including enhanced capacity retention, lower activation energy for lithium-ion diffusion, and higher compressive strength. A novel strategy for the preparation of high-performance monocrystalline NCM811 cathode materials is proposed in this work.