Improved Ionic Conductivity of PEO/Sulfonamide Lithium Salt Hybrid by the Addition of LiTFSI

Poly(ethylene oxide) (PEO) with the average molecular weight of 500, 1000, or 1900 having methane sulfonamide lithium salt in both chain ends was used as matrix to solubilize lithium bis-(trifluoromethane sulfonyl) imide (LiTFSI). Ionic conductivity of the above-mentioned PEO/salt hybrid was improved by the addition of LiTFSI. These mixtures were amorphous and lost the melting point of PEO part. The ionic conductivity was from 4 to 30 times higher than that of hybrid without LiTFSI since the number of carrier ions increased without remarkable elevating the glass transition temperature.