PVDF粉体预辐照接枝甲基丙烯酸缩水甘油酯制备锂离子二次电池隔膜研究

Study on lithium-ion secondary battery separator prepared by graft polymerization of GMA onto PVDF powder under pre- irradiation

以聚偏氟乙烯(PVDF)粉体为基材,采用预辐照接枝方法,在PVDF粉体上用乳液聚合接枝甲基丙烯酸缩水甘油酯(GMA),并采用溶液铸膜的方法制备了PVDF-g-PGMA膜。利用红外光谱(FTIR),扫描电子显微镜(SEM),压汞仪,电导率测试等分析表征手段对制备的PVDF-g-PGMA膜进行了表征。在氩气手套箱中组装成扣式电池,在电池测试系统上测试扣式电池的充放电循环性能。测试结果表明,在相同制备条件下,以PVDF-g-PGMA作为隔膜的锂离子电池性能优于以PVDF作为隔膜的锂离子电池性能。

PVDF-g-PGMA powder was prepared by pre-irradiation graft polymerization technique and then the membranes were cast from PVDF-g-PGMA powder with different degrees of grafting （DG） using solvent evaporation method. The structure and the performance both of the PVDF and the PVDF-g-PGMA membranes were analyzed by means of Fourier transform infrared spectroscopy （FT-IR）, scanning electron microscope （SEM）, mercury porosimetry and lithium ion conductivity, respectively. After assembling 2032 coin type cell, the battery performances were also investigated. The results demonstrate that the PVDF-g-PGMA membranes possess better cell performance than pristine PVDF membrane.