Efficient Synergy of In Situ Spinel Coating and Mo ⁶⁺ Doping for Improved Electrochemical Performance of Lithium-Rich Manganese-Based Cathode Materials

Lithium-rich manganese-based (LMR) cathode materials stand as promising candidates for future high-energy-density lithium-ion batteries; however, their commercialization is hindered by inherent electrochemical deficiencies. To address these challenges, strategies such as coating and doping, leveraging their respective modification advantages, have been employed to rectify specific shortcomings of cathode materials. Among these, the synergistic combination of coating and doping strategies has been explored to further enhance modification effects. In this study, we utilized ammonium molybdate to pretreat the surface of LMR cathode materials, achieving an efficient synergy of in situ spinel coating and molybdenum doping, which significantly improved the cycling performance (92.0% capacity retention for 200 cycles at 1 C) and rate capability (150 mA·h/g at 5 C) of the electrode materials. According to testing results and density functional theory (DFT) calculations, the ammonium molybdate pretreatment enhanced the electrical conductivity of the cathode materials. This strategy boasts a straightforward process and achieves an efficient synergism between coating and doping, offering a valuable reference for the practical production of multiply modified electrode materials in the future.