Construction of core-shell nanofiber membrane with enhanced interface compatibility for lithium-metal battery

Improving interface compatibility is critical to the solid-state lithium metal batteries. Thus, a novel type of core-shell nanocomposite polymer fiber membrane was prepared by a coaxial electrospinning technique. The coreshell nanofiber membranes contains poly (propylene carbonate) (PPC) in the shell, and poly(vinylidene fluorideco-hexafluoropropylene) (PVDF-HFP) that containing in-situ generated silica in the core. The structure, topography and compositions of the sample were investigated by scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). The nanocomposite membranes exhibit three-dimensional framework structure with well-dispersed fibers, and could be transformed readily into gel polymer electrolytes (GPEs) by being soaked in an ionic liquid solution. Our study showed that the core-shell PVDF-HFP-SiO2@PPC polymer electrolyte exhibited a relatively high electrolyte uptake of 460%. The core-shell electrolyte was found to play a significant role in increasing the interface compatibility. The optimized core-shell PVDF-HFP-SiO2@PPC electrolyte exhibited an enhanced ionic conductivity (1.05 mS cm(-1)) in comparison with the blend PVDF-HFP-SiO2-PPC electrolyte (0.5 mS cm(-1)) M 25 degrees C. This study demonstrates that the optimization of composition and microstructure is efficient in the fabrication of high-performance membranes for lithium-metal batteries.