LITHIUM SECONDARY BATTERY HAVING IMPROVED HIGH-TEMPERATURE STORAGE CHARACTERISTICS

WIPO Patent Application WO/2019/151725

A1

The present invention relates to a lithium secondary battery comprising: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; and a non-aqueous electrolyte, the positive electrode containing a positive electrode active material represented by chemical formula 1 below, the non-aqueous electrolyte containing a non-aqueous organic solvent, a first lithium salt, lithium bis(fluorosulfonyl)imide as a second lithium salt, and an additive, wherein the molar ratio of the first lithium salt : the second lithium salt is 1:0.01 to 1:1, and the additive is a mixed additive containing fluorobenzene, tetravinyl silane, and tertiary butyl benzene at a weight ratio of 1:0.05:0.1 to 1:1:1.5. [Chemical formula 1] Li(NiaCobMnc)O2 In chemical formula 1, 0.65