Optimizing Lithium-Ion Battery Discharge Capacity Performance by Nanosilica-Modified Poly (Vinyl Alcohol) Separator

In this research, pure and composite separators based on poly (vinyl alcohol) (PVA) and silica nanoparticles were made by using non-solvent induced phase separation (NIPS) method. The research carried out includes examining Field emission scanning electron microscopy (FESEM) images, pores diameter distribution, porosity measurement, electrolyte uptake, electrolyte retention, contact angle with electrolyte, thermal shrinkage, X-ray Diffraction (XRD) analysis, Energy dispersive X-ray spectroscopy (EDX) analysis and charge and discharge analysis of the resulting lithium-ion batteries. The results obtained indicate improved performance, with increased polymer or silica concentrations leading to enhanced pore characteristics and lithium-ion battery discharge capacity density. According to the battery charge and discharge analysis, at rates of 0.1 C, 0.2 C, 0.5 C the discharge capacity density for a lithium-ion battery consisting of commercial PP separator (Celgard 2500) was 180, 172, 166 mA h g⁻¹ and for optimized composite separator was 200, 188, 174 mA h g⁻¹.