Polyvinilidine fluoride (PVDF) nanofiber membrane for Li-ion rechargeable battery separator

Abstract

This study reported synthesis and characterization of PVDF (polyvinilidine fluoride) nanofiber membrane using electrospinning method for Li-ion rechargeable battery separator. Electrospinning equipment system consists of a DC high voltage (HV - DC), a controllable spinner and a plate collector. The effects of the applied voltage on morphological property, porosity and thermal property were systematically investigated. The application of DC voltage at a range of 13 to 17 kV resulted the one-dimension nanostructure of the PVdF nanofiber. The produced PVdF nanofiber membrane separators are evaluated to have a higher level of porosity (86 - 93%) and a good thermal shrinkage property in comparison to Polypropylene (PP) microporous membrane separator. The produced PVdF membrane separators were assembled into the LiFePO4 cells and demonstrated high charge-discharge capacities at room temperature with the coulombic efficiency reaching 80 %.