基于聚酰亚胺改性聚烯烃复合隔膜的制备及其性能  

Preparation of polyolefin composite separator modified by polyimide and their properties

作　　者：徐明礼 李琇廷 董杰[1] 滕翠青[1] 张清华[1] 赵昕[1] XU Mingli;LI Xiuting;DONG Jie;TENG Cuiqing;ZHANG Qinghua;ZHAO Xin(State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Materials Science and Engineering,Donghua University,Shanghai,China)

机构地区：[1]东华大学纤维材料改性国家重点实验室,材料科学与工程学院,上海

出　　处：《东华大学学报(自然科学版)》2025年第1期22-30,共9页Journal of Donghua University(Natural Science)

基　　金：上海市自然科学基金(22ZR1403200)。

摘　　要：合成含三氟甲基和苯并咪唑结构的聚酰亚胺(PI)作为涂层,对商业化聚烯烃(PE)隔膜进行表面涂覆,探究不同固含量的涂覆液对涂层孔隙结构、物理性能及电化学性能的影响。结果显示:当PI溶液的质量分数为11.1%时,综合性能最优,相较于PE隔膜,复合隔膜具有较佳的热稳定性,150℃的收缩率仅为13%左右,800℃后的残炭率为27.2%,远高于PE隔膜;复合隔膜的离子电导率与离子迁移数分别达0.18 mS/cm和0.77;利用复合隔膜组装的电池具有与PE隔膜相当的倍率性能,且在1 C倍率下、循环300圈后的容量保持率为86.0%,在锂对称循环测试中,电池在工作1000 h后,表现出更加稳定的脱(嵌)锂工作,能够形成稳定的固体电解质界面(solid electrolyte interface,SEI)层,并诱导锂的均匀沉积,从而提高电池的安全性和使用寿命。Polyimide(PI)containing trifluoromethyl and benzimidazole structures were synthesized as the raw materials of the coating and the commercial polyethylene(PE)separators was modified with the obtained PI solution.The effects of different solid contents of PI solutions on the pore structure of the coating and the physical and electrochemical properties of the composite separators were investigated.The results show that the composite separator obtained by PI solution of 11.1%displays optimal comprehensive performance.Compared with PE separator,the composite separator can inhibit thermal shrinkage at high temperature with the shrinkage rate of about 13%at 150℃and the carbon residue rate of 27.2%after 800℃,which are much higher than those of PE separator.The ionic conductivity and ion mobility number of the composite separator are 0.18 mS/cm and 0.77,respectively.The cell assembled using composite separator has a rate performance comparable to that with PE separator and its capacity retention rate is 86.0%after 300 cycles at a 1 C rate.In lithium symmetric cycle testing,the battery exhibits more stable lithium insertion/delithiation after 1000 h of operation,forming a stable(solid electrolyte interface,SEI)layer and inducing uniform deposition of lithium dendrites,thereby improving the safety and service life of the battery.

关 键 词：聚酰亚胺 聚烯烃 复合隔膜 热稳定性 电化学性能 

分 类 号：O633[理学—高分子化学]