Modified TiO2-SiO2 ceramic filler for a composite gel polymer electrolytes working with LiMn2O4

Abstract

A new type of ceramic filler (TiO2-SiO2) was used in composite gel polymer electrolytes for application in lithium-ion batteries (LiMn2O4|Li). TiO2-SiO2 ceramic powders were obtained by co-precipitation from solutions of titanium sulphate and sodium silicate. The resulting submicron-size powders were used as fillers in composite gel polymer electrolytes for Li-ion batteries based on polyacrylonitrile (PAN) membranes and sulpholane (TMS). The composite gel polymer electrolytes (PE) were analysed structurally and electrochemically, demonstrating favourable properties in terms of electrolyte uptake and electrochemical characteristics in Li-ion cells. The surface morphology of the PE was studied using scanning electron microscopy (SEM). It was found to be a stable, porous and flexible polymer electrolyte with an ionic conductivity of 9.8 × 10−4 S cm−1 at 25 °C. The performance of the LiMn2O4|PE3|Li cell was tested using electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge. The LiMn2O4 cathode exhibited good cyclability and coulombic efficiency (ca. 145 mAh g−1 after 50 cycles) when used together with 1 M LiPF6 in PAN/TMS/TiO2-SiO2+ 8 wt.% VC.