TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Electrolyte: In the gel electrolyte, the L of the Chemical Formula (1) comprises a repeating unit selected from repeating units represented by Chemical Formulas (12 to 14), and combinations.R13 to R15=a residual group derived from a compound selected from ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, diethylene glycol, alkanediol, ethoxylated alkanediol, propoxylated alkanediol, trimethylol propane, ethoxylated trimethylol propane, propoxylated trimethylol propane, ditrimethylol propane, ethoxylated ditrimethylol propane, propoxylated ditrimethylol propane, pentaerythritol, ethoxylated pentaerythritol, propoxylated pentaerythritol, dipentaerythritol, ethoxylated dipentaerythritol, propoxylated dipentaerythritol, bisphenol A, ethoxylated bisphenol A, and propoxylated bisphenol A; andn1-n3=independently an integer ranging from 1 to 20.The additive is present in an amount of 0.1-10 wt.%, preferably 0.5-2 wt.% based on the total weight of the gel electrolyte. The gel polymer further comprises a repeating unit derived from a second monomer selected from compounds represented by Chemical Formulas (15 to 22) and combinations.R16 to R24=independently selected from hydrogen, substituted and unsubstituted 1-10C aliphatic organic groups, and substituted and unsubstituted 6-20C aromatic organic groups;T1-T7=independently selected from hydrogen, substituted and unsubstituted 1-20C aliphatic organic groups, and substituted and unsubstituted 6-30C aromatic organic groups; andn4-n6=independently an integer of 1 to 10.The gel polymer comprises the repeating unit derived from the first monomer and the repeating unit derived from the second monomer in a weight ratio of about 85:15 to about 50:50. The non-aqueous organic solvent comprises gamma-butyrolactone, where the gamma-butyrolactone is present in an amount of 5-60 wt.% based on the total weight of the non-aqueous organic solvent containing the gamma-butyrolactone. The gel electrolyte has a viscosity of 4-20 cp. EXAMPLE - No suitable example given.