Effect of silica nanoparticles/poly(vinylidene fluoride-hexafluoropropylene) coated layers on the performance of polypropylene separator for lithium-ion batteries  

作　　者：Hongyu Liu Zehui Dai Jun Xu Baohua Guo Xiangming He 

机构地区：[1]Department of Chemical Engineering, Tsinghua University [2]Institute of Nuclear and New Energy Technology, Tsinghua University

出　　处：《Journal of Energy Chemistry》2014年第5期582-586,共5页能源化学（英文版）

基　　金：supported by the Tsinghua University Initiative Scientific Research Program(Grant No.2012THZ08129)

摘　　要：In an effort to reduce thermal shrinkage and improve electrochemical performance of porous polypropylene （PP） separators for lithium-ion batteries, a new composite separator is developed by introducing ceramic coated layers on both sides of PP separator through a dip-coating process. The coated layers are comprised of heat-resistant and hydrophilic silica nanoparticles and polyvinylidene fluoride-hexafluoropropylene （PVDF-HFP） binders. Highly porous honeycomb structure is formed and the thickness of the layer is only about 700 nm. In comparison to the pristine PP separator, the composite separator shows significant reduction in thermal shrinkage and improvement in liquid electrolyte uptake and ionic conduction, which play an important role in improving cell performance such as discharge capacity, C-rate capability, cycle performance and coulombic efficiency.In an effort to reduce thermal shrinkage and improve electrochemical performance of porous polypropylene （PP） separators for lithium-ion batteries, a new composite separator is developed by introducing ceramic coated layers on both sides of PP separator through a dip-coating process. The coated layers are comprised of heat-resistant and hydrophilic silica nanoparticles and polyvinylidene fluoride-hexafluoropropylene （PVDF-HFP） binders. Highly porous honeycomb structure is formed and the thickness of the layer is only about 700 nm. In comparison to the pristine PP separator, the composite separator shows significant reduction in thermal shrinkage and improvement in liquid electrolyte uptake and ionic conduction, which play an important role in improving cell performance such as discharge capacity, C-rate capability, cycle performance and coulombic efficiency.

关 键 词：composite separator silica nanoparticles DIP-COATING thermal shrinkage cell performance 

分 类 号：TM912[电气工程—电力电子与电力传动] O613.72[理学—无机化学]