Enhanced cycling stability and rate performance of Co-doped and La2O3-coated LiNi0.9Mn0.1O2 toward power battery

Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries (LIBs). However, the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability, which limits its application in practice. In this paper, the dual-modification strategy of Co doping and La 2 O 3 coating is used to meet the above challenges. Co doping can effectively widen layer spacing and reduce Li + /Ni 2+ mixing, and La 2 O 3 coating can effectively eliminate the residual alkali on the surface of active material, inhibit the thickening of cathode electrolyte interphase (CEI) film and reduce surface/interface side reactions. Therefore, the modified material (NM90-CL) with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La 2 O 3 coating. Its capacity retention rate can reach 77.9% after 200 cycles at 1.0 °C and 75.7% after 200 cycles at 5.0 °C. Its reversible capacity can up to 153.5 mAh·g –1 at 10.0 °C. This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials. Graphical abstract