Performance enhancement of PEO: LiDFOB based nanocomposite solid polymer electrolytes via incorporation of POSS-PEG13.3 hybrid nanoparticles for solid-state Li-ion batteries

Abstract

The addition of organic-inorganic hybrid nanoparticles presents a promising avenue for enhancing both the ionic conductivity at room temperature and the mechanical resilience of solid polymer electrolytes (SPEs). In this study, a novel nanocomposite solid polymer electrolytes (NSPEs) based on poly(ethylene oxide)-lithium difluoro(oxalato)borate (PEO₂₀-LiDFOB) incorporating polyhedral oligomeric silsesquioxane–poly(ethylene glycol) (POSS–PEG_13.3) hybrid nanoparticles were developed. And also reported the effect of POSS-PEG_13.3 hybrid nanoparticles on the structural, thermal, electrical, mechanical, and electrochemical properties of the (PEO₂₀-LiDFOB) SPE. X-ray diffraction (XRD), differential scanning calorimetry analysis (DSC) and polarized optical microscopy (POM) revealed that the POSS-PEG_13.3 hybrid nanoparticles greatly reduced the crystallinity. The NSPE with 40 wt% of POSS-PEG_13.3 exhibit markedly improved thermal stability and Young's modulus compared to electrolytes without the POSS-PEG_13.3 component. The NSPE with 40 wt% of POSS-PEG_13.3 exhibits the maximum ionic conductivity of 1.41 × 10⁻⁵ S/cm at 30 °C. The electrochemical stability of the optimum conducting composition is 3.8 V. The cell provided a maximum discharge capacity of 158 mAh g⁻¹ at 0.1C-rate with extremely good capacity retention up to 50 cycles. According to the test results, the electrolyte was determined to be a better contender than conventional organic liquid electrolytes for lithium-ion batteries.