基于聚丙烯腈纤维膜的高强度复合隔膜的制备  

Preparation of High Strength Composite Separator Based on Polyacrylonitrile Fibrous Membrane

作　　者：吴宽 王翔[1] 李子鸣 李艳玲 许龙 王钧[1] WU Kuan;WANG Xiang;LI Ziming;LI Yanling;XU Long;WANG Jun(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,Hubei,China;School of Physics and Physical Engineering,Qufu Normal University,Qufu 273165,Shandong,China)

机构地区：[1]武汉理工大学材料科学与工程学院,湖北武汉430070 [2]曲阜师范大学物理工程学院,山东曲車273165

出　　处：《武汉大学学报（理学版）》2020年第4期331-337,共7页Journal of Wuhan University:Natural Science Edition

基　　金：国家自然科学基金(51672201)。

摘　　要：静电纺丝聚丙烯腈(PAN)纤维膜具有孔隙率高和电解液吸收率高等优点,但纤维膜的强度差,难以满足隔膜在装配过程中的受力要求。以PAN纤维膜为基体,通过开环聚合反应引入聚环氧乙烷(PEO)和SiO2填料,制备了拉伸强度达到14. 7 MPa的新型PAN/PEO-SiO2复合隔膜,该复合隔膜在高温下具备优异的尺寸稳定性。电化学交流阻抗测试表明:与PAN纤维膜相比,复合隔膜的离子电导率更高,达到2. 72 mS/cm;该复合隔膜与锂金属电极之间的界面电阻仅为146Ω,小于PAN纤维膜。电池充放电性能测试表明:PAN/PEO-SiO2复合隔膜在高放电倍率(2. 0 C)时放电比容量仍有112. 1 mAh/g,与低放电倍率(0. 2 C)时相比,容量保留率到达75. 3%;在放电倍率0. 5 C时循环50圈后放电比容量仍有141. 4 mAh/g。Electrospun polyacrylonitrile(PAN) fibrous membranes exhibit high porosities and electrolyte uptake, whereas they cannot meet mechanical properties requirements during assembly process because of weak mechanical ability. A novel composite separator was prepared by introducing polyethylene oxide(PEO) and SiO2 fillers into PAN fibrous membrane with a ring-opening polymerization. PAN/PEO-SiO2 composite separator shows a tensile strength of 14.7 MPa and excellent thermal dimensional stability at a high temperature. Compared with PAN fibrous membrane, the higher ionic conductivity of composite separator is 2.72 mS/cm, moreover, the composite separator exhibits a lower interfacial resistance with lithium electrode of 146 Ω. The chargedischarge tests of cells show that the cell with composite separator shows a discharge capacity of 112.1 mAh/g at the discharge rate of 2.0 C, keeping 75.3% of the capacity at 0.2 C. In addition, the composite separator-based cell has a discharge capacity of141.4 mAh/g at the discharge rate of 0.5 C.

关 键 词：静电纺丝 复合隔膜 开环聚合 拉伸强度 

分 类 号：O631.5[理学—高分子化学]