Enhancing LiNiO2 cathode materials by concentration-gradient yttrium modification for rechargeable lithium-ion batteries

• 作者: Yudong Zhang Hang Li Junxiang Liu Jiuding Liu Hua Ma Fangyi Cheng
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（12）
• 页码范围: 312-319
• 页数: 8页
• 语种: 英文

摘要

Lithium nickel oxide (LiNiO2) cathode materials are featured with high capacity and low cost for rechargeable lithium-ion batteries but suffer from severe interface and structure instability.Here we report that rationally designed LiNiO2 via concentration-gradient yttrium modification exhibits allevia-tive side reactions and improved electrochemical performance.The LiNiO2 cathode with LiYO2-Y2O3 coat-ing layer delivers a discharge capacity of 225 mAh g-1 with a high initial Coulombic efficiency of 93.4％.These improvements can be attributed to the formation of in-situ modified hybrid LiYO2-Y2O3 coating layer,which suppresses phase transformation,electrolyte oxidation and salt dissociation due to the for-mation of protective cathode electrolyte interface.The results indicate promising application of concentration-gradient yttrium coating as a facile approach to stabilize nickel-rich cathode materials.