Two comb polymers with oligo-oxyethylene side chains of the type -O-(CH2-CH2-O)(n)-CH3 were prepared from poly(methylhydrosiloxane) (PMHS). Homogeneous polymer electrolytes were made from the two synthesised polymers and four lithium salts having different chemical structures, such as lithium perchlorate (LiClO4), lithium trifluoromethanesulfonate (LiCF3SO3), lithium hexafluorophosphate (LIPF6) and lithium bis(trifluoromethane sulfonylimide-) (LiN(SO2CF3)(2)) by solvent casting method, and their thermal, electrical and electrochemical properties measured as a function of temperature. Results indicate that polymer electrolyte complexes are amorphous materials, and that its properties depend on the oligo-oxyethylene chain length as well as on the chemical nature of the lithium salt.