Improved Cycling Stability of Layered Ni‐Rich Oxide Cathodes by Lithium Reactive Coating Layer via Atomic Layer Deposition

Abstract

The potential of high‐nickel‐layered LiNi 1– x – y Co y Mn z O 2 (with 1– x – y > 0.6, NCM) cathode as frontrunners for the high energy‐density lithium‐ion batteries (LIBs) lies in their high theoretical specific capacity and working potential. However, an inherent challenge arises from the formation of residual lithium compounds, leading to issues such as capacity deterioration, and suboptimal to deposition rage characteristics. Herein, this study leverages the prowess of plasma‐enhanced atomic layer deposition (ALD) technology to effectively coat LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) particles with a lithium reactive Co 3 O 4 layer. Consequently, these interventions yield tangible enhancements in the cycling performance and thermal stability of NCM811 materials. At a current density of 1 C, the initial specific capacity witnesses a noteworthy ascent from 152.9 mAh g −1 for the uncoated electrode to 169.1 mAh g −1 for the NCM811 cathode with Co 3 O 4 coating. After cycling for 200 cycles, the capacity retention rates register at 55.79% and 80.84%, respectively, for the uncoated and coated electrodes. Notably, the impact of Co 3 O 4 extends to bolstering the thermal stability of NCM811. In essence, this study harnesses ALD technology to cultivate a Co 3 O 4 ‐coated environment for NCM811, elevating cycling performance and enhancing thermal stability. These advancements hold profound implications for the evolution of LIB technology.