The polymer electrolyte based on polyethylene oxide (PEO) complexed with conducting polyaniline (PANI) and salts of AgNO3 and NaNO3 has been prepared in different weight percentage ratios. The complexation is confirmed by infra-red and X-ray diffraction studies. Conductivity (dc) measurements are carried out using a two-probe technique in the temperature range 30-80 degrees C. Electrochemical cell parameters for battery application at room temperature are also been determined. The electric conductivities are 1.5 x 10(-5) S cm(-1) at 30 degrees C and 5.5 x 10(-2) S cm(-1) at 80 degrees C for a PEO:PANI (50:50) composite. The conductivity increases with increasing weight percentage of polyaniline in polyethylene oxide, which may be due to a strong hopping mechanism between the ether group of polyethylene oxide and conducting polyaniline. Samples are fabricated for battery application in configurations of Na:(PEO + PANI):(I-2 + C + sample) and their experimental data are measured using the Wagner polarization technique. (c) 2005 Elsevier B.V. All rights reserved.