Nonaqueous electrolyte, lithium-ion battery, battery module, battery pack, and apparatus

A nonaqueous electrolyte, comprising a nonaqueous solvent, a lithium salt, and an additive, wherein

• the nonaqueous solvent is a high oxidation potential solvent, wherein the high oxidation potential solvent is selected from one or more of compounds represented by formula I and formula II;
• in formula I, R1 and R2 are independently selected from unsubstituted, partially halogenated or fully halogenated alkyl groups having 1 to 5 carbon atoms, and at least one of R1 and R2 is a partially halogenated or fully halogenated alkyl group having 1 to 5 carbon atoms;
• in formula II, R3 is selected from partially halogenated or fully halogenated alkylidene groups having 4 to 6 carbon atoms;
• based on a total weight of the nonaqueous electrolyte, a weight percentage of the high oxidation potential solvent is at least 10%;
• the additive comprises a cyclic sulfate, wherein the cyclic sulfate is selected from one or more of compounds represented by formula III;
• in formula III, R4 is selected from unsubstituted, partially halogenated, or fully halogenated alkylidene groups having 2 to 6 carbon atoms;
• a halogen atom of the R2, R2, R3, and R4 is selected from one or more of F, Cl, Br, and I;
• and
• based on a total weight of the nonaqueous electrolyte, a weight percentage of the cyclic sulfate is 0.1% to 10%.