Tailored NMC core/shell cathode powder for long cycle life LIB batteries

Abstract

High-Ni NMC (LiNiMnCoO2) cathode materials offer excellent energy density but suffer from chemical and structural degradation due to Ni reactivity and Li/Ni cation mixing, leading to poor cycle life. Within the EU-funded PHOENIX project, core-shell NMC particles were developed to address these issues. A Ni-rich NMC90 core was stabilized by a Mn-rich NMC622 shell, maintaining high energy storage while reducing surface degradation. The synthesis used an oxalate-assisted two-step coprecipitation and in-situ Li-infiltration process. A thin WO3 interlayer was added before shell coating to prevent interdiffusion. XRD analysis showed successful R3m structure formation at 850 °C for both materials. Electrochemical testing confirmed improved cycling performance for core-shell NMC cathodes, especially with the WO3 interlayer