Performance optimization of Al–Y co-doped ZrO2-coated LiNi0.8Co0.1Mn0.1O2 cathode material for lithium-ion batteries

A solvent-free strategy combining dry ball milling and calcination is developed to fabricate an Al-Y co-doped ZrO 2 (Al-YSZ) coating on LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathodes. Structural characterizations confirm Al-YSZ induces NCM811 lattice expansion (unit cell volume + 0.00026 nm 3 ) and reduces cation mixing ( I (003) / I (104)  = 1.621). TEM shows a ~ 50 nm coating with intimate matrix contact. Electrochemically, it delivers 218.9 mAh/g at 0.1 C (21.7% higher than pristine), retains 161.5 mAh/g after 200 cycles at 1 C, and exhibits superior stability under 4.5 V (137.3 mAh/g after 200 cycles), 45 ℃ (64.5% retention), and 5 C (86.0% retention). Mechanisms involve enhanced interfacial stability, optimized Li + kinetics (diffusion coefficient 2.21 × 10 −12 cm 2 /s after cycling), and mitigated structural degradation. This scalable green strategy advances high-nickel cathode optimization.