NONAQUEOUS ELECTROLYTE AND LITHIUM SECONDARY BATTERY CONTAINING THE SAME

摘要

The present invention relates to a lithium secondary battery nonaqueous electrolyte for improving stability at high temperature, comprising: an organic solvent in which lithium salt is dissolved with 0.8 to 1.2 mol; and both LiODFB (Lithium difluoro(oxalato)borate) and LiBF4 (Lithium tetrafluoroborate) as an electrolyte additive. Accordingly, the nonaqueous electrolyte improves stability at high temperature and improves storage and cycle properties at high temperature even if it is driven at high voltage.