Dual phase polymer gel electrolyte based on non-woven poly(vinylidenefluoride-co-hexafluoropropylene)–layered clay nanocomposite fibrous membranes for lithium ion batteries

A new approach for fabricating polymer gel electrolytes (PGEs) based on electrospun poly(vinylidenefluoride-co-hexafluoropropylene) {P(VdF-co-HFP)} incorporated with layered nanoclay has been employed to enhance the ionic conductivity and electrochemical properties of P(VdF-co-HFP) without compromising its mechanical strength. The effect of layered nanoclay on properties of membranes has been evaluated by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Surface morphology of the membranes has been studied using field-emission scanning electron microscopy (FE-SEM). Polymer gel electrolytes are prepared by soaking the fibrous membrane into 1 M LiPF6 in EC/DEC. The electrochemical studies show that incorporation of layered nanoclay into the polymer matrix greatly enhanced the ionic conductivity and compatibility with lithium electrodes. The charge–discharge properties and cycling performance of Li/LiFePO4 cells comprising nanocomposite polymer gel electrolytes have been evaluated at room temperature.

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► P(VdF-co-HFP)–clay nanocomposite based electrospun membranes are prepared.
► The membranes are used as polymer gel electrolyte (PGE) in lithium ion batteries.
► The composite PGE shows ionic conductivity of 5.5 mS cm−1 at room temperature.
► Li/PGE/LiFePO4 cell delivers initial discharge capacity of 160 mAh g−1.
► The use of prepared electrolyte significantly improved the cell performance.