TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compositions: Cyclic sulfate compound is a compound of formula (I). Unsaturated sultone compound is a compound of formula (V). Phosphazene compound is a compound of formula (VI). Halogenated phosphoric acid ester compound is a compound of formula R14-O-P(=O)(OR15)(OR16) (VII). Non-aqueous electrolyte contains compound of formulae (VIII), X-O-P(=O)(F)2 (IX), (X), and/or formula (XI). Total content of cyclic sulfate compound and unsaturated sultone compound is 0.01-10 mass% of total amount of non-aqueous electrolyte. Total content of phosphazene compound and halogenated phosphoric acid ester compound is 0.01-30 mass% of total amount of non-aqueous electrolyte. Total content of compound of formulae (VIII)-(XI) is 0.01-10 mass% of total amount of non-aqueous electrolyte.R1, R2=H, 1-6C alkyl, formula (II), or formula (III);R1+R2=benzene ring or cyclohexyl ring through carbon atom of R1 bonding with carbon atom of R2;R3=halo, 1-6C alkyl, 1-6C halogenoalkyl, 1-6C alkoxy, or formula (IV);wavy line=bonding position;R4-R7=H, halo, or 1-6C alkyl;n=0-3;R8-R13=halo, alkyl, aryl, alkoxy, or aryloxy;R14-R16=alkyl optionally substituted by halo or aryl optionally substituted by halo;M=alkali metal;Y'=transition element or group 13-15 elements;b=1-3;m=1-4;n=0-8;q=0 or 1;R17=1-10C alkylene, 1-10C halogenated alkylene, 6-20C arylene, or 6-20C halogenated arylene all of which may contain substituent or hetero atom in the structure in which when q is 1 and m is 2-4, each may bond m-number of R17;R18=1-10C alkyl, 1-10C halogenoalkyl, 6-20C aryl, 6-20C halogenated aryl all of which may contain substituent or hetero atom in the structure in which when n is 2-8, each may bond together and n-number R18 may form a ring, or -Q3R19;Q1-Q3=O, S, or NR20;R19, R20=H, 1-10C alkyl, 1-10C halogenoalkyl, 6-20C aryl, or 6-20C halogenated aryl provided that each may bond together to form a ring, and R19 or R20 may contain greater than or equal to 2 substituent or hetero atom;X=alkali metal or 1-12C hydrocarbon;R21, R22=H, Me, Et, or propyl; andR23-R26=1-6C hydrocarbon, 1-3C alkyl optionally substituted by F, 6-12C aryl, H, F, or Cl provided that R23-R26 are not H simultaneously.