A fast Li-ion conducting Li7.1La3Sr0.05Zr1.95O12 embedded electrospun PVDF-HFP nanohybrid membrane electrolyte for all-solid-state Li-ion capacitors

Hybrid polymer electrolytes with high dimensional stability and low electrode/electrolyte interfacial resistance have drawn exceptional attention as an electrolyte for all-solid-state Li-ion capacitors. Herein, various weight percentages of Li(7.1)La(3)Sr(0.0)5Zr(1.95)O(12) (LLSZO) embedded electrospun PVdF-HFP/LiPF6 based nanohybrid polymer membrane electrolytes (esHPME) are prepared for Li-ion capacitors. Li7.1La3Sr0.05Zr1.95O12 (LLSZO) garnet is prepared by a simple wet combustion technique and its structure and phase purity is confirmed by XRD studies. The surface morphology is investigated by FE-SEM studies. The thermal stability test reveals that the addition of LLSZO in the electrospun PVdF-HFP nanohybrid membrane significantly improves its thermal stability. 15 wt.% of LLSZO/PVdF-HFP/LiPF6 nanohybrid membrane electrolyte exhibits the ionic conductivity of 2.94 x 10(-3)Scm(-1), which is higher than that of other wt.% of LLSZO embedded PVdF-HFP/LiPF6 nanohybrid membrane electrolytes. Its electrochemical potential window is found to be 4.5 V. A LiCoO2/esHPME (15 wt.% of LLSZO)/AC based Li-ion capacitor is assembled and its specific capacitance is found to be 68.75 Fg(-1) at the current density of 1 Ag-1 with similar to 80 % of its initial capacitance even after 1000 cycles of charging-discharging. These results reveal that 15 wt.% of LLSZO/PVdF-HFP/LiPF6 based nanohybrid membrane electrolyte can be used as a potential candidate to develop high performance all-solid-state flexible Li-ion capacitor.