Effect of Co/Mn content on electrochemical properties of Ni-rich LiNi_0.9Co_xMn_0.1-xO₂

Active cathode materials with ultra-high specific capacities, including nickel-rich substrates, are promising candidates for future high-energy density batteries. However, the poor stability of nickel-rich cathodes has limited the development of long-life batteries. Herein, the electrochemical properties of layered cathode materials were optimized by tuning the transition metal ratio (Co/Mn) in precursor preparation. The effects of transition metals Co and Mn on the specific capacities and cyclabilities of layered cathode materials were investigated by X-ray photoelectron spectroscopy (XPS) and Density Functional Theory (DFT) calculations. Keeping Co and Mn equal allows extreme nickel cathode materials to have the best performance. The as-obtained LiNi_0.9Co_0.05Mn_0.05O₂ cathode exhibited a high capacity of 221.0 mAh g⁻¹, combined with excellent interfacial structure and thermal stability. The enhanced nickel ions mechanism of the active cathode materials by transition metal regulation was clarified. Overall, the proposed materials containing transition metals with improved capacity and cycling stability are promising for the development of future advanced batteries.