Preparation and characterization of PEO-PMMA polymer composite electrolytes doped with nano-Al2O3

This paper presents the preparation and characterization of a series of PEO-PMMA composites containing different lithium salts (LiClO 4 or LiTFSI) with or without nano-Al 2 O 3 . Nano-Al 2 O 3 is added to the polymer electrolytes to alter the morphology, ionic conductivity , interfacial and thermal shrinkage properties. Nano-Al 2 O 3 can effectively improve the stability of the polymer electrolyte membrane interface. The tensile strength of the PEO-PMMA-LiTFSI-Al 2 O 3 electrolyte membrane is 3.24   MPa at room temperature . The study shows that the ion conductivities at room temperature for PEO-PMMA-LiTFSI (EO/Li +   =   10) and PEO-PMMA-LiTFSI-Al 2 O 3 (EO/Li +   =   10) are 6.71   ×   10 −7   S/cm and 9.39   ×   10 −7   S/cm, respectively. A good dimensional stability was observed for PEO-PMMA-LiTFSI with a thermal shrinkage of 8.7%. The electrochemical windows of PEO-PMMA-LiTFSI and PEO-PMMA-LiTFSI-Al 2 O 3 are all stable up to 4.6   V versus Li + /Li, which makes them good electrolyte candidates of lithium ion batteries with high-potential cathodes.