ELECTROLYTIC SOLUTION AND LITHIUM-ION SECONDARY BATTERY UTILIZING THE SAME

The present invention provides an electrolyte solution and a lithium ion secondary battery which maintain for a long period high battery characteristics represented by the discharge capacity retention rate after the charge/discharge cycle, and simultaneously achieve also the high safety represented by the flame retardation. The present invention provides an electrolyte solution containing a nonaqueous solvent, an electrolyte, a specific compound having a perfluoroalkyl group in the molecule, and an additive having a fluorine atom and/or a phosphorus atom in the molecule.