Abstract The conductivity of lithium ions in polyacrylonitrile (PAN) is examined. Using the d.c. polarization method, the electric transport coefficient was observed to be less than 0.05. X-ray diffraction analysis confirms that PAN-LiClO 4 has an amorphous structure. Fourier-transform infrared spectroscopy results indicate that Li + ions form bonds not only with the C≡N groups of the PAN, but also with CO groups of the dimethylformamide. The relationship between conductivity and temperature suggests that the conduction of Li + ions in PAN is achieved through the polymer backbone's segmental motion. Finally, the activation energy of PAN(LiClO 4) 0.2 is estimated to be 86 kJ/mol.