Tungsten Oxide Stabilization Interlayer for Improved Cycling Stability of Core–Shell Structured Ni-rich NMC Cathodes

Kurzfassung

To mitigate core–shell interdiffusion and structural instabilities in high-nickel NMC cathodes, an NMC90 core/NMC622 shell architecture featuring a functional tungsten oxide interlayer was synthesized via one-pot oxalate co-precipitation for the PHOENIX project. Electrochemical testing revealed that the tungsten oxide interlayer effectively suppresses core–shell interdiffusion, allowing the modified cathode to reach an 80% state of health at 44 cycles compared to 20 cycles for the uncoated sample (2.7-4.2 V at C/10). This protective interlayer offers a practical strategy for enhancing the cycling stability and longevity of next-generation high-Ni NMC cathodes.