用SEM、XRD、ICP、恒电流充放电方法对真空退火前后磁控溅射制备的锂离子电池用Sn负极薄膜材料的形貌、结构及循环性能进行研究。结果表明,经过200℃×8 h真空退火后,薄膜颗粒细化且均匀分布,薄膜中还出现了Cu6Sn5和Cu3Sn合金相的特征峰,改善了膜基结合力。相对于纯Sn电极,热处理后样品的首次放电容量和首次库仑效率均略有下降,分别为709 mAh/g和67%;从第2次到30次循环的容量保持率为87%,库仑效率维持在94%-99%,均优于纯Sn电极。
Morphology,crystal structure and cyclic performance of tin films prepared by magnetron sputtering as anodes of lithium ion battery before and after vacuum annealing were investigated by scanning electron microscopy(SEM),X-ray diffraction(XRD),inductively coupled plasma spectroscopy(ICP)atomic emission spectrometry and the galvanostatic charge/discharge(GC)measurements,respectively.The results show that after vacuum annealing at 200 ℃ for 8 h the particles in the films become fine and uniformity after annealing.The Cu6Sn5 and Cu3Sn phases in the films can improve the binding force between the film and substrate.It can be found by comparing the annealed tin film anode with the pure tin film anode that the initial discharge capacity and coulombic efficiency are 709 mAh/g and 67%,respectively,both lower than those of pure tin anode.After annealing the retention of discharge capacity from the 2nd cycle to the 30th cycle are 87% and the coulombic efficiency is in the range of 94%-99%,both better than those of pure tin anode.