Enhancing performance and stability of LiNi0.8Co0.1Mn0.1O2 cathode via Na/Y dual doping for Lithium-Ion batteries

Abstract

Nickel-rich layered oxide cathode materials face limitations in practical applications due to trade-offs between capacity and structural stability. As more Li+ is extracted during charging, the layered structure of nickel-rich materials becomes increasingly fragile. To address this, a double doping strategy with Na and Y is proposed in this study to enhance the strength of the layered structure. The research findings demonstrate that Na doping enlarges the spacing between Li layers in the crystal structure, while Y doping improves the reversibility of the H2-H3 phase transition but narrows the Li layer spacing in nickel-rich materials. Na and Y double doping, the advantages of Na in enlarging the Li layer, and Y in improving the H2-H3 phase transition can be harnessed simultaneously. This double doping strategy ensures that the laminar structure of the cathode material remains stable even when it is highly detached, effectively solving the trade-off between the capacity and structural stability of nickel-rich laminar cathode materials. The application in LiNi0.8Co0.1Mn0.1O2 shows that the capacity and cycle life of cathode materials can be significantly improved after Na/Y double doping. These findings open up opportunities for practical applications of nickel-rich cathode materials in lithium-ion batteries.