TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - The electrolyte salt is a lithium metal salt.    TECHNOLOGY FOCUS - POLYMERS - Preferred Solution: The solution comprises the siloxane-modified polyoxyalkylene compound (at least 0.001 vol.%). EXAMPLE - A reactor was charged with allyl end-capped polyoxyethylene of formula H2C=CH-CH2O-(C2H4O)2-CH2-CH=CH2 (100 g), toluene (100 g) and a solution (0.05 g) of chloroplatinic acid (0.5 wt.%) in isopropyl alcohol (IPA). With stirring at 100degreesC, pentamethyldisiloxane (138 g) of H-Si((CH3)2)O-Si(CH3)3 was added dropwise to the mixture. Reaction took place while the molar ratio of terminal unsaturated groups to SiH groups was 1. The reaction solution was precision distilled in vacuum, obtaining the siloxane-modified polyoxyethylene of formula (CH3)3SiO-Si((CH3)2)-C3H6O-(C2H4O)2-C3H6-Si((CH3)2)-Si(CH3)3 having viscosity of 10.1 mm2/s and a purity of 99.7%. A non-aqueous electrolytic solution was prepared by dissolving (vol.%) the siloxane-modified polyoxyethylene (10) in ethylene carbonate (45) and diethyl carbonate (45) and further dissolving LiPF6 in it in a concentration of 1 mole/liter. The positive electrode material used was a single layer sheet using LiCoO2 as the active material and Pioxcel C-100 (RTM: an aluminum foil) as the current collector. The negative electrode material used was a single layer sheet using graphite as the active material and Pioxcel A-100 (RTM: a copper foil) as the current collector. The separator used was GC-50 (RTM: a glass fiber filter). A battery of 2032 coin type was assembled in a dry box blanketed with argon, by stacking the positive electrode material, separator and negative electrode material on a stainless steel can housing also serving as a positive electrode conductor, feeding the electrolytic solution, closing the opening with a stainless steel sealing plate also serving as a negative electrode conductor and an insulating gasket, and fastening and securing them tight. The steps of charging (up to 4.2 volts with a constant current flow of 0.6 mA) and discharging (down to 2.5 volts with a constant current flow of 0.6 mA and at a discharge rate of 0.15 C) at 25degreesC were repeated 10 cycles, after which similar charging/discharging steps were repeated at 5degreesC. Provided that the discharge capacity at the 10th cycle at 25degreesC was 100, the number of cycles repeated until the discharge capacity at 5degreesC lowered to 80 was counted. For comparison, a battery of 2032 coin type was assembled using a non-aqueous electrolytic solution not containing the siloxane-modified polyoxyethylene, and similarly tested. As a result, the battery with the siloxane-modified polyoxyethylene-containing non-aqueous electrolytic solution marked 205 cycles whereas the battery with the non-aqueous electrolytic solution not containing the siloxane-modified polyoxyethylene marked 85 cycles.