长寿命及高功率锂离子电池用多孔石墨烯/聚偏氟乙烯功能层复合隔膜  

A graphene/PVDF/PP multilayer composite separator for long-life and high power lithium-ion batteries

作　　者：步爱秀 谭勇[2] 方若翩 李峰[1] 裴嵩峰[1] 任文才[1] 

机构地区：[1]中国科学院金属研究所沈阳国家材料科学国家(联合)实验室,辽宁沈阳110010 [2]沈阳理工大学,辽宁沈阳110159

出　　处：《新型炭材料》2017年第1期63-70,共8页New Carbon Materials

摘　　要：隔膜是锂离子电池的重要组成部分,对隔膜进行材料及结构的优化可以提高锂离子电池的性能。通过在普通商用聚丙烯(PP)隔膜表面构建多孔石墨烯/聚偏氟乙烯功能层的方式获得了复合隔膜材料,通过涂布及常温液相处理的方法调控涂层的孔隙结构,使复合隔膜对电解液的吸附性能明显提高,功能层使复合隔膜具有优异的离子透过性和单侧(石墨烯层)导电性。与采用普通聚丙烯隔膜相比,功能层复合隔膜在低倍率(0.5 C)下的电极材料容量发挥相当。而在高倍率(5 C)下,功能层复合隔膜下,电池容量发挥非常突出,并且600次循环后的容量保持率接近100%,而采用常规PP隔膜,电池材料则容量快速衰减失效。The separator is an important part of lithium-ion batteries and its optimization from both material and structural consid-erations can improve the performance of the battery. We prepared multilayer separators by coating a slurry containing graphene and PVDF in N-methylpyrrolidone on one side of a commercial polypropylene （PP） separator,fol low ed by water trea tment at 60 ℃ for 6 h and vacuum drying at 60℃ for 12 h to manipulate the pores tructure of the comp o s ite layer. Results indic a te that the discharge capacities of batteries using PP and the composite separator were nearly the same at a low rate of 0.5 C. However,th ecapacity of the former at a high rate of 5 C fades quickly while that of the latter remains almost unchanged after 600 cycles. The composite sepa-rators have a high absorption and wettability of the electrolyte, resulting in an improved conductivity.

关 键 词：锂离子电池 复合隔膜 石墨烯/聚偏氟乙烯 孔隙结构调控 离子电导率 

分 类 号：TM912[电气工程—电力电子与电力传动]