SECONDARY BATTERY

摘要

Provided are: an electrolyte solution for lithium ion secondary batteries, which contains 65-99 vol% of a phosphoric acid ester compound, 0.01-30 vol% of a fluorinated carbonate compound, and 0.1-10 vol% of a halogenated phosphoric acid ester compound and/or 0.1-30 vol% of a solvent having a relative dielectric constant of 15 or more; and a lithium ion secondary battery which comprises the electrolyte solution for lithium ion secondary batteries.