Enhanced Electrochemical Performance of Y-Doped and ZrO 2 -Coated Lithium-Rich Manganese-Based Layered Oxide Cathode Materials for Lithium-Ion Batteries

Extensive research interest has been garnered by lithium-rich manganese-based layered oxides (LMNC), primarily driven by their high specific capacity and economic advantage. However, LMNC suffers from severe irreversible oxygen release, surface–interface side reactions, and structural degradation, which lead to rapid voltage and capacity fading during cycling, significantly hindering their commercial application. Herein, a synergistic modification strategy of “Yttrium doping–ZrO2 coating” is proposed for the Y-LMNC@ZrO2 composite cathode. First-principle calculations confirm that Y-doping enhances lattice oxygen stability owing to the strong Y–O bond, effectively suppressing oxygen loss during delithiation. Meanwhile, the ZrO2 coating layer considerably reduces side reactions at the electrode–electrolyte interface. Experimental results show that after 200 cycles at 1C, the Y-LMNC@ZrO2 electrode exhibits an excellent electrochemical performance, achieving a high discharge capacity of 172.3 mAh g–1 and maintaining a capacity retention of 92.34% after cycling. In full-cell tests, the Y-LMNC@ZrO2 sample exhibits an 13.36% improvement in capacity retention after 100 cycles compared with the unmodified sample. These results demonstrate that as-prepared Y-LMNC@ZrO2 is a promising high-performance cathode material for lithium-ion batteries.