AlF3包覆 LiNi1／3 Co1／3 Mn1／3 O2正极材料及其电化学性能

摘要

采用喷雾干燥法制备 LiNi 1／3 Co1／3 Mn1／3 O2正极材料，溶胶—凝胶法制备 AlF3包覆LiNi 1／3 Co1／3 Mn1／3 O2正极材料。通过 XRD、SEM、电化学测试等对 AlF3包覆 LiNi 1／3 Co1／3 Mn1／3 O2正极材料的结构、形貌和电化学性能进行研究。结果表明：AlF3包覆 LiNi 1／3 Co1／3 Mn1／3 O2正极材料为α-NaFeO2型结构，属空间群。样品为类球形，颗粒大小均匀。包覆后的样品首次放电容量略有降低，但是显著提高了其循环性能，其首次充放电容量为148 mA·h ／g，25次充放电循环后容量保持率为93．9％。%Layemred-LiNi 1 /3 Co1 /3 Mn1 /3 O2 was prepared by spray drying method and AlF3-coated LiNi 1 /3 Co1 /3 Mn1 /3 O2 was synthesized by sol-gel method. The structure, morphology and electrochemical properties of LiNi 1 /3 Co1 /3 Mn1 /3 O2 ,was studied by using X-ray diffraction,scanning electron microscopy and charge-discharge experiments.The results indicate that layered crystal structure of material with α-NaFeO2 type.Samples have spherical types and uniform particle sizes.The first discharge capacity of AlF3-coated Li 1 /3 Ni 1 /3 Co1 /3 Mn1 /3 O2 is lower than the uncoated material slightly,but the cycle performance was improved greatly.The initial capacity is 148 mA·h /g and the capacity retention is about 93.9% after 25 cycles.