高纯氧化铝涂覆层对锂电池聚乙烯隔膜的影响  

Effect of High Purity Alumina Coating on Polyethylene Diaphragm of Lithium Battery

作　　者：张瑞珠[1] 冯家赫 李炎炎 马淑云 ZHANG Rui-zhu;FENG Jia-he;LI Yan-yan;MA Shu-yun(North China University of Water Resources and Electric Power,Zhengzhou 450045,China;Henan Tianma New Material Co.,Ltd,Zhengzhou 450041,China)

机构地区：[1]华北水利水电大学,郑州450045 [2]河南天马新材料股份有限公司,郑州450041

出　　处：《表面技术》2021年第9期162-168,共7页Surface Technology

基　　金：郑州市重点实验室资助项目([2014]3-10);河南省工程技术研究中心资助项目(2016-221-35);第三批智汇郑州1125·聚才计划-创新紧缺人才资助项目([2018]-45-15)。

摘　　要：目的提高电池隔膜的安全性能。方法采用聚乙烯隔膜为基膜,用聚丙烯酸酯和高纯氧化铝制备涂覆液,研发出单侧的高纯氧化铝涂层隔膜,用穿刺力测试仪CCY-02检测隔膜的穿刺强度,用XLW智能电子拉伸力试验机测定隔膜的拉伸强度,用TQD-G1透气度测试仪检测隔膜的透气度,并称量计算隔膜吸液率,室温下采用RSY-R1热缩实验仪检测隔膜的热缩性,研究了涂覆层的引入对隔膜机械性能、热稳定性、透气度以及水分含量等的影响,并通过傅里叶变换红外光谱仪(FTIR)、X射线能谱分析仪(EDS)及扫描电镜(SEM)对复合隔膜的成分及微观形貌进行表征。结果引入高纯氧化铝涂覆层后,复合隔膜的综合性能得到明显改善,当涂覆溶液中聚丙烯酸酯的添加量为6%、高纯氧化铝的添加量为40%时,隔膜的整体性能达到最佳,耐穿刺强度值到达785 g,横向拉伸强度为158.6 MPa,纵向拉伸强度为121.7 MPa,透气度为263 s/100 mL,吸液率为300%;在130℃的真空条件下保存1 h,其横向热收缩为2.18%,纵向收缩为0.83%。对涂覆前后的电池隔膜进行微观表征发现,经高纯氧化铝涂覆后的隔膜表面形成了分布均匀的微孔结构,对锂离子在正负两极之间的转移起到促进作用。结论由于氧化铝本身的物化特性,对锂电池隔膜的耐热性有一定的提高,引入高纯氧化铝涂覆层后,锂离子电池隔膜的综合性能得到了极大改善。To improve the safety performance of the battery diaphragm,polyethylene diaphragm is used as base membrane,polyacrylate and alumina are used as coating solution to develop one side high purity alumina coating diaphragm.Puncture strength of diaphragm is measured by CCY-02 puncture force tester,tensile strength of diaphragm is measured by XLW intelligent electronic tensile force tester,permeability of diaphragm is measured by TQD-G1 air permeability tester,liquid absorption rate of diaphragm is calculated by weighing;thermal shrinkage of diaphragm is detected by RSY-R1 thermal shrinkage tester at room temperature to study the mechanical properties,thermal stability,air permeability and moisture content of diaphragm by introducing coating layer.The microscopic characterization of the composite diaphragm was studied by FTIR,EDS,and SEM.After the high purity alumina coating was introduced,the comprehensive performance of the composite diaphragm is obviously improved:When the amount of polyacrylate in the coated solution is 6%and the amount of pure alumina is 40%,the overall performance of the diaphragm is optimal,puncture strength reached 785 g,transverse tensile strength of 158.6 MPa with the longitudinal tensile strength of 121.7 MPa,air permeability of 263 s/100 mL,the suction rate of 300%.Under vacuum at 130℃for 1 h,the transverse thermal contraction is 2.18%,vertical collection shrink is 0.83%.The results of analysis the component and microscopic characterization of the composite diaphragm show that the surface of the modified membrane forms a well-distributed microporous structure,which promotes the transfer of lithium ions between positive and negative poles.Because of the physicochemical characteristics of alumina,the heat resistance of lithium battery diaphragm is improved.Therefore,the high purity alumina composite diaphragm plays a positive role.In general,the comprehensive performance of lithium ion battery diaphragm is greatly improved after the introduction of high purity alumina coating.

关 键 词：锂电池 聚乙烯 高纯氧化铝 聚丙烯酸酯 涂层 复合隔膜 

分 类 号：TG174.4[金属学及工艺—金属表面处理]