Non-aqueous electrolyte, secondary battery and electrical apparatus

A non-aqueous electrolyte comprising a first additive and a second additive, wherein the first additive is a cyclic sulfate compound having a structure represented by general formula (I),

• in the general formula (I), R1, R2, R3 and R4 are each independently selected from any one of a group having a structure represented by general formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group and a sulfonic acid group, and
• in the general formula (II), R5 and R6 are each independently selected from any one of a group having the structure represented by the general formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group and a sulfonic acid group;
• R1 and R2 are not both hydrogen atoms and R3 and R4 are not both hydrogen atoms;
• the second additive is selected from a phosphate compound, an isocyanate compound or a combination thereof;
• the phosphate compound has a structure represented by general formula (III):
• in the general formula (III), R1, R2, R3, R4 and R5 are each independently selected from any one of a group having a structure represented by general formula (IV), a hydrogen atom, a C1-C6 alkyl group, a halogen atom, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C6-C10 aryl group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxy group, a sulfonic acid group, and a tris(C1-C6 alkyl)silyl group;
• in the general formula (IV), R6, R7, and R8 are each independently selected from any one of a hydrogen atom, a C1-C6 alkyl group, a halogen atom, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C6-C10 aryl group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group;
• the isocyanate compound has a structure represented by general formula (V):
• in the general formula (V), R1 is selected from the following groups which are unsubstituted or substituted by one or more Ra:
• a C2-C10 alkylene group, a C2-C10 heteroalkylene group, a C6-C18 arylene group, a C2-C18 heteroarylene group, a C3-C18 alicyclylene group, and a C3-C18 heteroalicyclylene group,
• the one or more Ra are each independently selected from a halogen atom, —CN, —NCO, —OH, —COOH, —SOOH, a C2-C10 ester group, a C1-C10 alkyl group, a C2-C10 alkenyl group, a C2-C10 alkynyl group, and a C2-C10 alkoxy group;
• and
• in the general formula (V), n is 1, 2 or 3.