Electrolyte and lithium secondary battery

摘要

An electrolyte with excellent ionic conductivity, and a lithium secondary battery utilizing the electrolyte for increased level of safety. The lithium secondary battery comprises a positive and a negative electrode that reversibly intercalate and deintercalate lithium, and an electrolyte containing a lithium ion. The electrolyte comprises: a polymer having a carbonate group represented by formula 1 below: where R₁ is a hydrocarbon group with a carbon number of 2 to 7, and n is an integer from 10 to 10000; an electrolyte salt; and an organic solvent. The electrolyte salt is contained with a molar ratio of 0.2 or more with respect to the carbonate group, thereby providing the battery with an excellent ionic conductivity and high levels of safety.