ADDITIVES FOR LITHIUM SECONDARY BATTERY

摘要

Disclosed is a lithium secondary battery comprising a cathode (C) , an anode (A) , a separator and an electrolyte, wherein the electrolyte comprises: (a) a nitrile group- containing compound and (b) a compound having a reaction potential of 4.7V or higher. The lithium secondary battery can prevent the problems caused by a nitrile group-containing compound added to the electrolyte for the purpose of improving high-temperature cycle characteristics and safety (such problems as a battery swelling phenomenon and a drop in recovery capacity under high-temperature (>80°C) storage conditions) , by adding a fluorotoluene compound.