Non-aqueous electrolyte solution and non-aqueous electrolyte secondary battery employing the same

A non-aqueous electrolyte solution, comprising:

• an electrolyte;
• a non-aqueous solvent;
• vinylene carbonate;
• (A) a compound having at least two isocyanate groups per molecule;
• and
• (B) at least one compound represented by formula (5);
• R5≡R6 (5)
• wherein:
• R5 and R6 are each independently a hydrogen atom, a halogen atom, or an optionally substituted organic group, such that one of R5 and R6 in formula (5) is, or both of R5 and R6 in formula (5) are, an organic group having at least one S═O group:
• the non-aqueous electrolyte solution comprises from 0.01 mass % or more to 5 mass % or less of the compound (B) of formula (5), based on a total mass of the non-aqueous electrolyte solution;
• the compound (A) having at least two isocyanate groups per molecule comprises at least one selected from the group consisting of hexamethylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, dicyclohexylmethane-4,4′-diisocyanate, bicyclo[2.2.1]heptan-2,5-diylbis(methyl isocyanate), bicyclo[2.2.1]heptan-2,6-diylbis(methyl isocyanate), isophorone diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and a polyisocyanate compound derived therefrom;
• and
• a weight ratio of the compound (A) having at least two isocyanate groups per molecule to the compound (B) of formula (5) ranges from 1:30 to 1.5:1.