Non-aqueous electrolyte additive, non-aqueous electrolyte and lithium ion battery

The invention provides a non-aqueous electrolyte additive, a non-aqueous electrolyte and a lithium ion battery. The non-aqueous electrolyte additive is used for being compounded with fluorine-containing lithium salt, and comprises an additive A, an additive B and an S-containing auxiliary additive, r1 is not equal to R2 of the additive A, and R1 and R2 can be independently selected from any one of alkane, alkylene, aromatic hydrocarbon, pyridine, pyrrole, thiophene, thiazole and imidazole; r5, R6 and R7 of the additive A can be independently selected from any one of alkane, alkylene and halogen fluorine atom substitution. According to the non-aqueous electrolyte additive, the additive A, the additive B and the S-containing auxiliary additive are combined for use, so that a very good synergistic effect can be achieved, and trace water in a non-aqueous electrolyte of a lithium ion battery as well as HF, acid and byproduct water generated in a circulating process can be removed; therefore, the lithium ion batter