EVOH-SO3Li/PET电纺锂离子电池隔膜电化学性能

摘要

EVOH-SO3 Li/PET Li-ion battery composite membranes were prepared by means of alternated electrostatic spinning,then the morphology of the membranes was observed by scanning electron microscope,and the electrochemical properties of the membranes were tested by using an electrochemistry work station.The results show that the average diameter of EVOH-SO3Li/PET fibre is 387nm,both two kinds of fibres exhibit uniform net-like structure.Compared with pure EVOHSO3Li fibre,adhesion phenomenon of modified EVOH-SO3 Li/PET fibre is not obvious anymore,and the surface of EVOH-SO3Li/PET fibre becomes more smooth with enlarged pores between adjacent fibres;the electrochemical window of EVOH-SO3Li/PET separator is 5.3V,bulk resistance of EVOH-SO3Li/PET is decreased to 212.31Ω,and the ion conductivity of EVOH-SO3Li/PET separator is 2.347 × 10-3 S/cm,the properties of EVOH-SO3Li/PET membranes are improved compared with EVOH-SO3Li.%采用聚对苯二甲酸乙二醇酯(PET)与乙烯-乙烯醇共聚物的磺化物(EVOH-SO3Li)进行交替静电纺丝,制备EVOH-SO3Li/PET复合锂离子电池隔膜,通过扫描电子显微镜对隔膜的微观形貌进行观察,并利用IM6型电化学工作站对隔膜的电化学性能进行分析测试.结果表明:EVOH-SO3Li/PET纤维膜的平均直径为387nm,两种纤维均呈现均匀的网状结构.相比纯EVOH-SO3Li纤维,改性后EVOH-SO3Li/PET复合纤维之间粘连现象明显降低,且纤维表面更加光滑,纤维间孔隙增大;组装的锂离子电池的电化学稳定窗口为5.3V,界面阻抗降至212.31Ω,离子电导率则提高至2.347×10-3S/cm,与EVOH-SO3Li隔膜相比各项性能均有所提高.