Nanoscale Y-doped ZrO₂ modified LiNi_0.88Co_0.09Al_0.03O₂ cathode material with enhanced electrochemical properties for lithium-ion batteries

LiNi_0.88Co_0.09Al_0.03O₂ is one of the most promising and practical candidates to be applied as next-generation cathodes for lithium-ion batteries due to its high discharge specific capacity (approximately 210 mAh g⁻¹), energy density and low cost. Nevertheless, severe capacity fading and poor rate performance are the major barriers for their large-scale application. Herein, a simple and sufficient mechanical mixing method is adopted to prepare a nanoscale Y-doped ZrO₂ modified LiNi_0.88Co_0.09Al_0.03O₂ cathode material with enhanced electrochemical performance. The crystal structures, surface morphologies and electrochemical properties of the bare and modified materials are also characterized. The results confirm that the as-prepared Y-doped ZrO₂ modified LiNi_0.88Co_0.09Al_0.03O₂ cathode material delivers an initial discharge specific capacity of 215.1 mAh g⁻¹ with a coulombic efficiency of 91.8% between 2.5 and 4.3 V. The cycling stability is also remarkably enhanced with a capacity retention from 67.5% to 85.5% after 100 cycles at 1 C rate. Further investigations indicate that the aforementioned excellent performance can be attributed to suppressing impedance increase by stabilizing the cathode material from unfavorable side reactions with the electrolyte and preventing the propagation of intergranular cracking without hindering lithium-ion diffusion.