LITHIUM SECONDARY BATTERY

摘要

PURPOSE: A lithium secondary battery is provided to reacts when the battery is overcharged and forms a polymer layer which has a radical trap effect in cathode, thereby obtaining safety of the battery. CONSTITUTION: A lithium secondary battery comprises positive electrodes(1), negative electrodes(2), electrolyte, and polymerizable compound or a polymer. The polymerizable compound comprises a compound which contains aromatic functional group and polymerizable functional group and a compound which contains halogen-containing functional group and polymerizable functional group. The polymer comprises a compound which contains halogen-containing functional group and moiety of the aromatic functional group and the polymerizable functional group. The polymerizable compound additionally includes a highly polar functional group and the polymerizable functional group. The polymer additionally includes a highly polar functional group.