TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The amount of disulfonyl compound and the disulfinyl compound in the electrolytic solution is 0.0005-8 mass%. The non-aqueous solvent includes compounds including a first unsaturated cyclic ester carbonate compound of formula (III), a second unsaturated cyclic ester carbonate compound of formula (IV), a third unsaturated cyclic ester carbonate compound of formula (V), a halogenated cyclic ester carbonate compound of formula (VI), and a halogenated chain ester carbonate compound of formula (VII). The electrolyte salt includes lithium bis(fluorosulfonyl)imide. The cathode, the anode and the electrolytic solution are contained inside a film-like outer package member. (I) includes N-fluorosulfonyl-N-methyl-sulfamoyl fluoride, N-ethyl-N-fluorosulfonyl-sulfamoyl fluoride, N-fluorosulfonyl-N-propyl-sulfamoyl fluoride, N-fluorosulfonyl-N-vinyl-sulfamoyl fluoride, N-fluorosulfonyl-N-phenyl-sulfamoyl fluoride, N-fluorosulfonyl-N-pentyl-sulfamoyl fluoride, (bis(fluorosulfonyl)amino)methyl acetate, N-acetonyl-N-fluorosulfonyl-sulfamoyl fluoride, (bis(fluorosulfonyl)amino)methyl methyl carbonate, 2-(bis(fluorosulfonyl)amino)ethyl methyl carbonate, N-fluorosulfonyl-N-(trifluoromethyl)sulfamoyl fluoride, N-benzyl-N-fluorosulfonyl-sulfamoyl fluoride, N-chlorosulfonyl-N-methyl-sulfamoyl chloride, (hydrosulfonyl-methyl-oxoboranyl-1,5-azanyl)sulfonyl-oxo-borane, N-iodosulfonyl-N-methyl-sulfamoyl iodide, N-fluorosulfonyl-N-(2-methoxyethyl)sulfamoyl fluoride, N-fluorosulfonyl-N-(4-methoxybutyl)sulfamoyl fluoride, and N-acetyl-N-fluorosulfonyl-sulfamoyl fluoride. (II) includes (bis(fluorosulfinyl)amino)methane, (bis(fluorosulfinyl)amino)ethane, 1-(bis(fluorosulfinyl)amino)propane, (bis(fluorosulfinyl)amino)ethene, (bis(fluorosulfinyl)amino)benzene, (bis(fluorosulfinyl)amino)benzene, (bis(fluorosulfinyl)amino)methyl acetate, 1-(bis(fluorosulfinyl)amino)-2-oxo-propane, 2-(bis(fluorosulfinyl)amino)methyl acetate, 2-2-(bis(fluorosulfinyl)amino)ethyl acetate, (bis(fluorosulfinyl)amino)-trifluoro-methane, (bis(fluorosulfinyl)amino)methylbenzene, (bis(chlorosulfinyl)amino)methane, 2-(bromo-bromosulfinyl-hydrosulfinyl-1,5-azanyl)methane, (bis(iodosulfinyl)amino)methane, (bis(fluorosulfinyl)amino)-methoxy-methane, (bis(fluorosulfinyl)amino)methoxymethoxyethane, and 1-(bis(fluorosulfinyl)amino)-1-oxo-ethane.R11, R12 = H or alkyl;R13-R16 = vinyl, allyl (both preferred), H, or alkyl;R17 = CR31R32;R31, R32 = H or alkyl; andR21-R30 = halo, halogenated alkyl (both preferred), H, or alkyl.