Electrolyte and electrochemical apparatus
An electrolyte including an additive of compound of formula I, wherein n is an integer ranging from 0 to 10; R 1 and R 2 are each independently selected from a substituted or unsubstituted C 1 -C 10 alkylidene group, a substituted or unsubstituted C 2 -C 10 alkenylene group, or a substituted or unsubstituted C 1 -C 10 alkyleneoxy group; A 1 selected from CH, C, N, S, O, B or Si; A 2 is selected from CH—R 3 , N—R 3 , S, O, B—R 3 or SiH—R 3 ; A 3 selected from CH 2 , CH, C, N, S, O, B or Si; R 3 is selected from hydrogen, halogen, a substituted or unsubstituted C 1 -C 10 alkyl group, or a substituted or unsubstituted C 3 -C 10 cycloalkyl group; X 1 is selected from a substituted or unsubstituted C 1 -C 10 alkylidene group, a substituted or unsubstituted C 2 -C 10 alkenylene group, ═R c ═, or ═R c —, wherein R c is selected from a substituted or unsubstituted C 2 -C 6 alkylidene group.
1. An electrolyte comprising at least one compound selected from the group consisting of:
a content of the at least one compound accounts for b % of a weight of the electrolyte, wherein b % is 0.1% to 5%; and
lithium difluorophosphate;
a content of the lithium difluorophosphate accounts for a % of the weight of the electrolyte;
wherein a range of a/b is 0.01-6.
2. The electrolyte according to claim 1 , wherein the content of the lithium difluorophosphate accounts for 0.01% to 1.5% of a weight of the electrolyte.
3. The electrolyte according to claim 1 , wherein the electrolyte further comprises a compound of formula II,
wherein R 4 , R 5 and R 6 are each independently selected from H, a cyano group, a substituted or unsubstituted C 1 -C 10 alkyl group, or —R a —X—R b , wherein R a is selected from a single bonded or a substituted or unsubstituted C 1 -C 10 alkylidene group, R b is selected from a cyano group, or a substituted or unsubstituted C 1 -C 10 alkyl group, and X is selected from O, S, a sulfone group, or a carbonate group, wherein when substituted, the substituent is selected from halogen or a cyano group, and at least one of R 4 , R 5 , and R 6 comprises a cyano group; and
a content of the compound of formula II accounts for 0.1% to 5% of a weight of the electrolyte.
4. The electrolyte according to claim 3 , wherein the compound of formula II comprises at least one selected from the group consisting of:
5. The electrolyte according to claim 1 , further comprising at least one selected from the group consisting of a compound of formula III, a compound of formula IV and a compound of formula V:
wherein R 7 and R 8 are each independently selected from a C 1 -C 10 alkyl group that is unsubstituted or substituted with one or more fluorine atoms, and at least one of R 7 and R 8 is substituted with fluorine;
R 9 and R 10 are each independently selected from a C 1 -C 10 alkyl group that is unsubstituted or substituted with one or more fluorine atoms, and at least one of R 9 and R 10 is substituted with fluorine;
m is an integer ranging from 0 to 5; and
a content of the compound of formula III accounts for less than or equal to 60% of a weight of the electrolyte,
a content of the compound of formula IV accounts for less than or equal to 60% of the weight of the electrolyte, and
a content of the compound of formula V accounts for less than or equal to 25% of the weight of the electrolyte.
6. The electrolyte according to claim 5 , wherein
the compound of formula III comprises at least one selected from the group consisting of:
the compound of formula IV comprises at least one selected from the group consisting of:
and
the compound of formula V comprises at least one of
7. An electrochemical apparatus, comprising a positive electrode, a negative electrode, and an electrolyte comprising at least one compound selected from the group consisting of:
a content of the at least one compound accounts for b % of a weight of the electrolyte, wherein b % is 0.1% to 5%; and
lithium difluorophosphate;
a content of the lithium difluorophosphate accounts for a % of the weight of the electrolyte;
wherein a range of a/b is 0.01-6.
8. The electrochemical apparatus according to claim 7 , wherein the electrolyte further comprises a compound of formula II,
wherein R 4 , R 8 and R 6 are each independently selected from H, a cyano group, a substituted or unsubstituted C 1 -C 10 alkyl group, or —R a —X—R b , wherein R a is selected from a single bonded or a substituted or unsubstituted C 1 -C 10 alkylidene group, R b is selected from a cyano group, or a substituted or unsubstituted C 1 -C 10 alkyl group, and X is selected from O, S, a sulfone group, or a carbonate group, wherein when substituted, the substituent is selected from halogen or a cyano group, and at least one of R 4 , R 5 , and R 6 comprises a cyano group; and
a content of the compound of formula II accounts for 0.1% to 5% of a weight of the electrolyte.
9. The electrochemical apparatus according to claim 7 , wherein the compound of formula II comprises at least one selected from the group consisting of:
10. The electrochemical apparatus according to claim 7 , wherein the electrolyte further comprising at least one of selected from the group consisting a compound of formula III, a compound of formula IV and a compound of formula V:
wherein R 7 and R 8 are each independently selected from a C 1 -C 10 alkyl group that is unsubstituted or substituted with one or more fluorine atoms, and at least one of R 7 and R 8 is substituted with fluorine;
R 9 and R 10 are each independently selected from a C 1 -C 10 alkyl group that is unsubstituted or substituted with one or more fluorine atoms, and at least one of R 9 and R 10 is substituted with fluorine;
m is an integer ranging from 0 to 5; and
a content of the compound of formula III accounts for less than or equal to 60% of a weight of the electrolyte,
a content of the compound of formula IV accounts for less than or equal to 60% of the weight of the electrolyte, and
a content of the compound of formula V accounts for less than or equal to 25% of the weight of the electrolyte.
11. The electrochemical apparatus according to claim 10 , wherein
the compound of formula III comprises at least one selected from the group consisting of:
the compound of formula IV comprises at least one selected from the group consisting of:
and
the compound of formula V comprises at least one of
12. The electrochemical apparatus according to claim 7 , wherein the positive-electrode comprises a positive-electrode active material containing an aluminum element, and the aluminum element accounts for 0.001% to 3% of a total weight of the positive-electrode active material.
13. An electronic apparatus, comprising an electrochemical apparatus, wherein the electrochemical apparatus, comprising a positive electrode, a negative electrode, and an electrolyte comprising at least one compound selected from the group consisting of
a content of the at least one compound accounts for b % of a weight of the electrolyte, wherein b % is 0.1% to 5%; and
lithium difluorophosphate;
a content of the lithium difluorophosphate accounts for a % of the weight of the electrolyte;
wherein a range of a/b is 0.01-6.