Study of the influence of different concentrations of Mg doping on the performance of LiNi0.9Mn0.1O2 cathode materials

Abstract

In recent years, nickel-rich, cobalt-free LiNi_0.9Mn_0.1O₂ (LNMO) cathode materials have garnered significant attention in the field of lithium-ion batteries due to their advantages, including high specific capacity, high operating voltage, and low cost. However, challenges such as low Coulomb efficiency during the initial cycling process, poor cycling stability, and significant voltage decay have hindered their broader commercialization. In this study, we have successfully synthesized the LNMO cathode materials for rechargeable lithium-ion batteries by a combination of the high-temperature solid-phase method and co-precipitation technique. The incorporation of Mg was applied to further improve the electrochemical properties of the LNMO material. The influence of different concentrations of Mg doping on the electrochemical properties of the product was systematically investigated. The results showed the 1% Mg-LNMO sample exhibited the most superior electrochemical performance. Additionally, EIS analysis showed that the 1% Mg-LNMO sample had the lowest impedance, indicating that Mg doping enhanced particle stability.