Development of NMC cathode powders with optimized core/shell architecture

Abstract

High-nickel LiNixMnyCozO2 (NMC) cathodes offer high storage capacity, cost efficiency, and reduced environmental impact. However, higher Ni content causes rapid capacity fading and poor thermal stability. To overcome these issues, a core/shell NMC cathode was synthesized, featuring a Ni-rich NMC90 core for high capacity and a Mn-rich NMC622 shell for structural stability. A cost-effective oxalate-assisted coprecipitation method was used, optimizing calcination temperature, time, and lithium content. Characterization via SEM, EDX, XRD, and GCD confirmed the formation of the R3m phase at 850 °C and a high I(003)/I(104) ratio, indicating improved ordering. The core/shell structure exhibited higher specific capacity and enhanced cycling stability, demonstrating a synergistic balance between energy density and durability.