Elastomeric electrolyte films consisting of maleic anhydride-g-poly (1, 2-butadiene) (MAPB) grafting polyethylene glycol 400 (PEG400) as matrix and LiClO4 as alkali salt at the mole ratio of [O]: [Li+] at 6, 8, and 10, respectively are prepared. An equivalent circuit is proposed based on the electronic impedance spectroscopy plots by using the metal/electrolyte film/metal model, the simulant plots are found matched well with the tested plots, and the conductivity variations with salt concentrations and temperatures are calculated accordingly. The film with the mole ratio of [O]: [Li+] at 8:1 exhibits higher conductivity at room temperature, due to its relatively stronger dissociation of oxygen atom to LiClO4 as supported by the FTIR spectroscopy. Their conductivity dependent on temperatures obeys the Arrhenius equation from 303 to 363 K, while it keeps almost unchanged at higher temperatures; these changes are found associate with the strong complexation of oxygen atom with Li+ and the state transference of MAPB elastomer as observed by the DSC analysis. Besides, these films are still thermally stable at around 200 degrees C as observed by the TGA analysis and may be promising solid polymer electrolytes with high stability. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013