Grain‐growth Inhibitor with Three‐section‐sintering for Highly Dispersed Single‐crystal NCM90 Cubes

Abstract

Single crystallization of LiNixCoyMn1‐x‐yO2(NCM) is currently an effective strategy to improve the cycling life of NCM cathode, owing to the reduced surface area and enhanced mechanical strength, but the application of single crystal NCM(SC‐NCM) is being hindered by severe particle agglomeration and poor C‐rate performance. Here, a strategy of three‐section‐sintering(TSS) with the presence of grain‐growth inhibitor was proposed, in which, the TSS includes three sections of phase‐formation, grain‐growth and phase‐preservation. While, the addition of MoO3 inhibits the grain growth and restrains the particle agglomeration. With the help of TSS and 1 mol % of MoO3, highly dispersed surface Mo‐doped SC‐NCM(MSC‐NCM) cubes are obtained with the average diameter of 1.3 μm. Benefiting from the surface Mo‐doping and the reduced surface energy, the Li+‐migration preferred (1 0 4) crystalline facet is exposed as the dominant plane in MSC‐NCM cubes, because of which, C‐rate performance is significantly improved compared with the regular SC‐NCM. Furthermore, this preparation strategy is compatible well with the current industrial production line, providing an easy way for the large‐scale production of SC‐NCM.