Synthesis and electrochemical performance of YF3-coated LiMn2O4 cathode materials for Li-ion batteri

• 作 者: CAO Jina CAO Gaoshao YU Hongming XIE Jian ZHAO Xinbing
• 机 构: Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
• 出 处: 稀有金属（英文版）
• 发表日期: 2011年1期
• 关键词: lithium batteries coatings cathodes electrochemical properties

Spinel LiMn2O4 cathodes were coated with 1 mol% YF3. X-ray diffraction (XRD) analyses showed that Y and/or F did not enter the lattice of the LiMn2O4 crystal. Transmission electron microscopy (TEM) showed that a compact YF3 layer of 5-20 nm in thickness was coated onto the surface of LiMn2O4 particles. Scanning electron microscopy (SEM) observation showed that the YF3 coating caused the agglomeration of LiMn2O4 particles. The cycling test demonstrated that the YF3 coating can improve the electrochemical performance of LiMn2O4 at both 20 and 55℃. Moreover, YF3-coated LiMn2O4 exhibited an improved rate capability compared with the uncoated one at high rates over 5C. The immersion test in electrolytes showed that YF3-coated LiMn2O4 is more erosion resistant than the uncoated one.