LITHIUM ION BATTERY AND RELEVANT BATTERY MODULE, BATTERY PACK AND APPARATUS

The present application relates to an electrolytic solution including an organic solvent, a lithium salt and an additive, wherein the lithium salt comprises a primary lithium salt, the primary lithium salt is a first compound in an amount of 30% or more relative to the total molar amount of the lithium salt, and the first compound has a structure represented by the following formula I, and wherein the additive comprises a second compound represented by the following formula II. The present application further relates to a lithium ion battery comprising the electrolytic solution, especially those especially in the form of a high-nickel system.