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Lithium-conducting nanocomposite polymer electrolytes based on high molecular weight poly(oxyethylene) are prepared from high aspect ration cellulosic whiskers and lithium imide LiTFSI salt. The thermomechanical behavior of the resulting films is investigated by differential scanning calorimetry, thermogravimetric analysis and dynamics mechanical analysis.

Low-melting ionic liquid, IL, based on small aliphatic quaternary ammonium cations ([R(1)R(2)R(3)NR](+), where R(1), R(2), R(3) = CH(3) or C(2)H(5), R = C(3)H(7), C(4)H(9), C(6)H(13), C(8)H(17), CF(3)C(3)H(6)) and imide anion were prepared and characterized. The physicochemical and electrochemical properties of these ILs, including melting point, glass transition, and degradation temperatures; viscosity; density; ionic conductivity; diffusion coefficient; and electrochemical stability, were determined. Heteronuclear Overhauser NMR spectroscopy experiments were also performed to point out the presence of pair correlation between the different moieties. The LiTFSI addition effect on the IL properties was studied with the same methodology. Some nanoscale organization with segregation of polar and apolar domains was observed. ILs with small alkyl chain length or fluorinated ammonium exhibit very high electrochemical stability in oxidation.