Solvent for nonaqueous electrolyte solution of lithium secondary battery

Abstract

The present invention provides a solvent for a nonaqueous electrolyte solution enabling a lithium secondary battery to exhibit an excellent discharge capacity, load characteristics, and cycle characteristics even under high voltages, as well as a nonaqueous electrolyte solution that uses this solvent and a lithium secondary battery. This solvent for a nonaqueous electrolyte solution is a solvent for a nonaqueous electrolyte solution for a lithium secondary battery, wherein the solvent for a nonaqueous electrolyte solution contains a fluorine-free cyclic carbonate (I), a fluorine-free chain carbonate (II), and a 1,1-di(fluorinated alkyl)ethylene carbonate (III), and wherein with a sum of (I), (II), and (III) being 100 volume %, the fluorine-free cyclic carbonate (I) is 10 to 50 volume %, the fluorine-free chain carbonate (II) is 49.9 to 89.9 volume %, and the 1,1-di(fluorinated alkyl)ethylene carbonate (III) is from at least 0.1 volume % to not more than 30 volume %.

Dependencies are inferred from the claim text.