Impedance and FTIR studies on plasticized PMMA-LiN(CF3SO2)2 nanocomposite polymer electrolytes

Plasticized polymer electrolytes composed of poly(methyl methacrylate) (PMMA) as the host polymer and lithium bis(trifluoromethanesulfonyl)imide LiN(CF3SO2)(2) as a salt were prepared by solution casting technique at different ratios. The ionic conductivity varied slightly and exhibited a maximum value of 3.65 x 10(-5) S cm(-1) at 85% PMMA and 15% LiN(CF3SO2)(2). The complexation effect of salt was investigated using FTIR. It showed some simple overlapping and shift in peaks between PMMA and LiN(CF3SO2)(2) salt in the polymer electrolyte. Ethylene carbonate (EC) and propylene carbonate (PC) were added to the PMMA-LiN(CF3SO2)(2) polymer electrolyte as plasticizer to enhance the conductivity. The highest conductivities obtained were 1.28 x 10(-4) S cm(-1) and 2.00 x 10(-4) S cm(-1) for EC and PC mixture system, respectively. In addition, to improve the handling of films, 1% to 5% fumed silica was added to the PMMA-LiN(CF3SO2)(2)-EC-PC solid polymer electrolyte which showed a maximum value at 6.11 x 10(-5) S cm(-1) for 2% SiO2.