Fabrication and Characterization of P(VDF-HFP)-SiO2 Electrospun Composite Membrane for Li-ion Batteries

The performance of electrospun polymeric fibers as membranes in lithium-ion batteries (LIBs) has attracted much attention in recent decades due to their high surface to volume ratio and high porosities. For this reason, electrospinning has more advantages than other membrane fabrication methods such as dry, wet and so on; but the intrinsic low mechanical strength and large pore size of these membranes limit their battery performance. The production of poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP) composite membranes with various percentages of silica (SiO2) nanoparticles by electrospinning method can be promising strategy to decrease these constraints. In this paper, P(VDF-HFP)-SiO2 electrospun composite membranes have been fabricated and the effect of SiO2 content on different properties have been investigated. Surface Morphology of composite membrane is characterized by scanning electron microscopy (SEM) and shows that the produced fibers are stacked in layers to produce fully interconnected pores resulting in high porosity. The heat treatment of electrospun P(VDF-HFP)-SiO2 composite membranes at high temperatures indicates that these membranes have better thermal stability than P(VDF-HFP) membranes. Also, physical and mechanical evaluation of P(VDF-HFP)-SiO2 composite membranes shows that addition of SiO2 nanoparticles to P(VDF-HFP) fibers increases porosity but decreases puncture strength of produced membranes.

Keywords:

Membrane , Electrospinning , Li-ion Battery , P(VDF-HFP) , SiO2