PEO-hBN-NaClO4 Polymer Composite Electrolyte for Sodium Ion Batteries

A new polymer electrolyte (conducting sodium-ion) based on Polyethylene oxide (PEO) matrix comprising NaClO4 and nano sized hexagonal boron nitride was fabricated via the technique of solution casting for use in sodium ion batteries. Interaction of PEO with Na-ion was investigated with fourier transform infrared (FT-IR) which reveals the extend of Na-ion solvation by PEO (EO:Na). The crystallinity of the polymer electrolyte was investigated with X-ray diffraction (XRD) and thermal properties of the composites were studied with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The DSC results show that the melting temperature (Tm) of PEO decreases addition of both NaClO4 and hBN. TGA results showed that all the composites membranes were thermally stable till 300 oC. Surface morphology of the composite was examined using scanning electron microscopy (SEM) which also reveals the homogeneous dispersion of nano hBN in the polymer matrix. Ionic conductivity of the polymer composite was studied with impedance spectroscopy and PEO5hBN10Na sample showed maximum ion conductivity of approximately 1.4 × 10-3 S/cm at 100 oC