SBA-15, due to its ordered mesoporous structure and potential for advanced applications in separation technologies, catalysis, and nanoscience, has attracted much attention in the past few years. In this work, a novel PEO-based composite polymer electrolyte has been developed by using SBA-15 as the filler. The interactions between SBA-15 and PEO matrix are studied by XRD, DSC, and FT-IR techniques in detail. The effects of SBA-15 on the electrochemical properties of the PEO-based polymer electrolyte, such as ionic conductivity, lithium ion transference number, and interfacial stability with lithium electrode, are studied by electrochemical impedance spectroscopy and steady-state current method. The experiment results show that the addition of SBA-15 can enhance the ionic conductivity and increase the lithium ion transference number of PEO-based polymer electrolyte at the same time. The excellent performances such as high mechanical stability, good compatibility with lithium metal electrode, and broad electrochemical stability window suggest that PEO-LiClO4/SBA-15 composite polymer electrolyte can be used as candidate electrolyte material for lithium polymer batteries. (c) 2005 Elsevier B.V. All rights reserved.