A composite polymer electrolyte of Polyethylene oxide (PEO) LiClO 4 containing fine Al 2O 3 particles was studied by using differential scanning calorimetry, infrared spectroscopy and electrochemical impedance spectroscopy. Compared with the polymer electrolyte without Al 2O 3 particles, the glass transition temperature and the degree of crystallinity were decreased, and the room temperature conductivity of PEO LiClO 4 Al 2O 3 composite polymer electrolyte was considerably enhanced. Moreover, the equivalent circuits and the effect of dc potential on impedance spectroscopy were discussed.
