蒙脱石纳米片/聚偏氟乙烯改性聚丙烯复合隔膜的制备及性能研究  

Preparation and Performance of Montmorillonite Nanosheet/PVDF−Polypropylene Composite Separator

作　　者：孔静 李宇恒 胡雅祺 王蕊[1] 陈天星 KONG Jing;LI Yuheng;HU Yaqi;WANG Rui;CHEN Tianxing(School of Resources Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,Shaanxi,China)

机构地区：[1]西安建筑科技大学资源工程学院,陕西西安710055

出　　处：《矿产保护与利用》2023年第6期107-113,共7页Conservation and Utilization of Mineral Resources

基　　金：国家自然科学基金青年基金项目(52104267)。

摘　　要：商用聚烯烃隔膜表现出较差的电解液浸润性和大幅的热收缩性,不利于锂离子电池的安全高效运行。利用天然矿物独特的晶体结构、良好的润湿性、优异的热稳定性和机械稳定性,在聚烯烃隔膜表面涂覆天然矿物材料是增强隔膜性能的方法之一。采用刮涂法制备了复合隔膜(MMT-PVDF/PP),对复合隔膜的机械性能、润湿性能、热稳定性等性能进行了研究。结果表明:当涂布液中蒙脱石纳米片和黏结剂的质量比为5∶5时,复合隔膜表面形成了MMT-PVDF三维稳定结构,相比聚丙烯隔膜(PP),MMT-PVDF/PP复合隔膜的拉伸强度提升了6倍,吸液率和保液率分别提升了24.93百分点和96.7百分点。复合隔膜在150℃环境下1h后仍能维持较好的尺寸形态,收缩率不到10%。Commercial polyolefin separators exhibit poor electrolyte wettability and severe thermal shrinkage,which are not conducive to the safe and efficient operation of lithium−ion batteries.Using the unique crystal structure,good wettability,excellent thermal and mechanical stability of natural minerals,coating raw mineral materials on the surface of polyolefin separators is one of the methods to enhance the performance of the separators.The composite separator(MMT−PVDF/PP)was prepared by scraping coating method,and the mechanical properties,wettability,thermal stability of the composite separator were investigated.The results showed that when the mass ratio of montmorillonite nanosheets and binder in the coating solution was 5∶5,a three−dimensional stabilized structure of MMT−PVDF was formed on the surface of the composite separator.Compared with polypropylene separators(PP),the tensile strength of the MMT−PVDF/PP composite separator was increased by 6 times,and the electrolyte uptake and retention rate were increased by 24.93%and 96.7%,respectively.The composite separator can maintain a good dimensional morphology at 150℃for 1h with less than 10%shrinkage.

关 键 词：锂离子电池 聚烯烃隔膜 电解液润湿性 热收缩性 

分 类 号：TD985[矿业工程—选矿] TQ320.72[化学工程—合成树脂塑料工业]