二次锂电池用PVDF-HFP/SiO_2复合聚合物隔膜的研究  

Study of PVDF-HFP/SiO_2 Composite Polymer Separator for Rechargeable Lithium Battery

作　　者：李立[1] 苑克国[2] 张育川[1] 胡塔光[1] 王安邦[2] 杨裕生[2] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029 [2]防化研究院军用化学电源研究与发展中心,北京100083

出　　处：《北京化工大学学报（自然科学版）》2006年第2期55-58,63,共5页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家'863'计划项目(2001AA320301)

摘　　要：采用倒相法制备了二次锂电池用的聚偏氟乙烯-六氟丙烯复合聚合物(PVDF-HFP/SiO2)隔膜,测定了它的吸液率、电导率、机械强度等性能,并通过扫描电镜对其形貌进行了分析。研究结果表明:PVDF-HFP/SiO2隔膜具有较高的吸液率、电导率和韧性,电解质吸收率达184.4%,室温电导率为1.20 mS/cm,断裂伸长率高达163%。利用PVDF-HFP/SiO2隔膜装配的二次锂电池的首放比容量为834.8 mAh/g,第40次的放电比容量达到400 mAh/g,循环效率达到99.8%以上,表现出良好的电化学性能。A polymer （PVDF-HFP） separator and a composite polymer （PVDF-HFP/SiO2） separator were prepared by the phase-inversion method. The electrolyte uptake, conductivity and mechanical properties of the separators were studied, and the corresponding micro-structures were examined by SEM. The PVDF-HFP/SiO2 separator exhibits much higher electrolyte uptake, conductivity and ductibility with an electrolyte uptake volume of 184.4 %, a conductivity of 1.2 mS/cm and ductibility of 163 %. When the PVDF-HFP/SiO2 separator is employed in a lithium battery a good cycle performance and a high cycling efficiency are observed. The first discharge specific capacity is 834.8 mAh/g, the 40th cycle discharge capacity is 400 mAh/g and the average charge/discharge efficiency is above 99.8 %

关 键 词：复合聚合物隔膜 纳米SIO2 二次锂电池 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ325.4[化学工程—合成树脂塑料工业]