NONAQUEOUS ELECTROLYTE SOLUTION AND LITHIUM ION SECONDARY BATTERY

摘要

A nonaqueous solvent for use in a nonaqueous electrolyte solution of lithium ion secondary battery (1), comprising propylene carbonate (PC), a first compound of the chemical formula (I) and a second compound of the chemical formula (II), wherein the content of PC is 10 vol.% or more and the content (mass%) of first compound, X, and the content (mass%) of second compound, Y, simultaneously satisfy the requirements of the mathematical formulae: 2 <= (X + Y) <= 8 (1) and 0.01 <= (Y/X) <= 0.30 (2). In the chemical formula (I), each of R<1> to R<6> represents any of a hydrogen atom and C1-C3 hydrocarbon groups. In the chemical formula (II), each of R<7> and R<8> represents any of a hydrogen atom and C1-C3 hydrocarbon groups.