The rapid capacity fading of the Ni-rich cathode has become the main obstacle to its development. Generally, the coating method can be used for modification, which can effectively isolate side reactions and maintain the original structure. In this study, novel rare earth (La, Ho, Tm) polymetallic oxide (REPMO) coating is topologically prepared on the surface of LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) by using high speed shearing with reduction method. After modification, the high-rate capacity at 5 C enhanced a lot (100.3 mA h g⁻¹ vs 31.2 mA h g⁻¹) which is 3.2 times higher. This is because the Ni²⁺ of the cathode could be changed into Ni³⁺ to reduce the mixing of Li⁺/Ni²⁺ and the structural stability has been improved. Moreover, the synergistic effect of REPMO coating can increase ionic conductivity, accelerate Li⁺ diffusion rate and inhibit the phase transition, cation mixing and volume shrinkage. Our work provides an innovative idea at this moment for the selection and synthesis method of coating material for modification of cathode material.

富镍正极的容量快速衰减已成为其发展的主要障碍。一般可以采用包覆的方法进行改性，可以有效隔离副反应，保持原有的结构。本研究采用高速剪切还原法在LiNi _0.8 Co _0.1 Mn _0.1 O ₂ (NCM811 )表面拓扑制备了新型稀土(La,Ho,Tm)多金属氧化物(REPMO)涂层。改性后，5 C高倍率容量大幅提升（100.3 mAh g ^-1 vs 31.2 mAh g ^-1），提高了3.2倍。这是因为阴极的Ni ^{2+可以转变为Ni 3+减少了Li +} /Ni ²⁺的混合，提高了结构稳定性。此外，REPMO涂层的协同效应可以增加离子电导率，加速Li ⁺扩散速率并抑制相变、阳离子混合和体积收缩。我们的工作此时为正极材料改性的涂层材料的选择和合成方法提供了创新思路。