Functional Passivation Interface of LiNi0.8Co0.1Mn0.1O2 toward Superior Lithium Storage

Abstract The fast capacity/voltage fading with a low rate capability has challenged the commercialization of layer‐structured Ni‐rich cathodes in lithium‐ion batteries. In this study, an ultrathin and stable interface of LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NCM) is designed via a passivation strategy, dramatically enhancing the capacity retention and operating voltage stability of cathode at a high cut‐off voltage of 4.5 V. The rebuilt interface as a stable path for Li + transport, would strengthen the cathode–electrolyte interface stability, and restrain the detrimental factors for cathode–electrolyte interfacial reactions, intergranular cracking and irreversible phase transformation from layered to spinel, even salt‐rock phase. The as‐optimized NCM displays a higher cyclability (i.e., 206.6 mA h g −1 at 0.25 C (50 mA g −1 ) with 92.0% capacity retention over 100 cycles) and a better rate capability (141.0 and 112.6 mA h g −1 at 12.5 and 25 C, respectively) than pristine NCM (205.0 mA h g −1 with 73.0% capacity retention at 0.25 C; 120.9 and 93.1 mA h g −1 at 12.5 and 25 C, respectively).