PE/PET Li-ion Battery Separator: Preparation by Wet Method and Electrospinning and Its Comparison with Industrial PP Separator

Lithium-ion batteries (LIB) have attracted enormous attention in the past decades due to their outstanding features, such as high energy density, long cycle life, low self-discharging capacity. Although Lithium-ion batteries have been an energy storage system for commercial electronics, issues regarding its safety raised doubt about its usage for energy storage. This paper presents a bilayer Li-ion battery separator produced by the wet method for its Polyethylene (PE) base layer, which has been reinforced by a nonwoven polyethylene terephthalate layer by electrospinning. This separator has appropriate porous morphology, 41% porosity, BET specific surface area of 39.3 m2/gr, an average pore diameter of 22 nm, electrolyte uptake of 216%, a tensile strength of 100 MPa, the ionic conductivity of 0.451 mS/cm, Excellent electrochemical stability up to 4.6 volts, acceptable cyclic performance and charge and discharge capacity which provides the expected characteristics of a suitable separator and, above all, due to the presence of a layer PET provides a shutdown safety window of about 100 degrees Celsius by improving its dimensional stability under high temperatures.