Free-standing, high Li-ion conducting hybrid PAN/PVdF/LiClO₄/Li_0.5La_0.5TiO₃ nanocomposite solid polymer electrolytes for all-solid-state batteries

The free-standing PAN/PVdF/LiClO₄/Li_0.5La_0.5TiO₃ nanocomposite solid polymer electrolytes have been prepared by solution casting technique. The thermal stability of composite solid polymer electrolytes is evaluated by TG/DSC analysis, which reveals that the filler incorporated composite samples exhibit high thermal stability up to 500 °C. The XRD analysis demonstrated that the Li_0.5La_0.5TiO₃ nanoparticles significantly reduced the crystallinity of the hybrid PAN/PVdF/LiClO₄ polymer films. The FTIR spectra of PAN/PVdF/LiClO₄/Li_0.5La_0.5TiO₃ composites show the vibrational band of –CN stretching, CF₂ asymmetric stretching, and Ti-O-La stretching which confirmed the complexation between polymer host matrices and Li_0.5La_0.5TiO₃ nanoparticles. The 10 wt% Li_0.5La_0.5TiO₃ nanoparticles embedded PAN/PVdF/LiClO₄ solid polymer electrolyte possessed an excellent ionic conductivity of 1.43 × 10⁻³ S cm⁻¹ at room temperature, which is far better than the filler-free samples (~ 10⁻⁵ S cm⁻¹). The incorporation of Li_0.5La_0.5TiO₃ nanoparticles into the PAN/PVdF/LiClO₄ polymer electrolyte improves the concentration of free mobile lithium ions and develops Li-ion conduction channels within the crystalline framework. The PAN/PVdF/LiClO₄/Li_0.5La_0.5TiO₃ (10 wt%) composite electrolyte exhibited high thermal stability, good discharge capacities of 122, 105, 94, and 80 mAh g⁻¹ at 0.1, 0.5, 1, and 2C rates, and good cycling stability.