Electrolyte and electrochemical apparatus

Patent metadata

Field	Value
Publication number	US-2023275269-A1
Application number	US-202117281548-A
Country	US
Kind code	A1
Filing date	Feb 3, 2021
Priority date	Apr 29, 2020
Publication date	Aug 31, 2023
Grant date	—

Abstract

An electrolyte, including an additive A, wherein the additive A comprises a non-fluorinated lithium borate compound; and at least one additive selected from an additive B, an additive C, an additive D, or an additive E, wherein the additive B comprises at least one of vinylene carbonate, fluoroethylene carbonate, lithium tetrafluoroborate, lithium difluoro(oxalato)borate, or lithium difluorophosphate; the additive C comprises a compound comprising S═O; the additive D comprises a compound having 2 to 4 cyano groups; and the additive E comprises a silicon-containing carbonate compound. This application provides an electrolyte and an electrochemical apparatus. The electrolyte includes additives such as a non-fluorinated lithium borate compound, thereby effectively improving high-temperature storage performance, cycle performance, floating charge performance and/or overcharge performance of the electrochemical apparatus.

First claim

1 . An electrolyte, comprising:
an additive A, wherein the additive A comprises a non-fluorinated lithium borate compound; and at least one additive selected from an additive B, an additive C, an additive D, or an additive E, wherein the additive B comprises at least one of vinylene carbonate, fluoroethylene carbonate, lithium tetrafluoroborate, lithium difluoro(oxalato)borate, or lithium difluorophosphate; the additive C comprises a compound comprising S═O; the additive D comprises a compound having 2 to 4 cyano groups; and the additive E comprises a silicon-containing carbonate compound.

2 . The electrolyte according to claim 1 , wherein the non-fluorinated lithium borate compound comprises at least one of a compound I-1, a compound I-2, a compound I-3, a compound I-4, or a compound I-5:

3 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive B; based on a total weight of the electrolyte, a weight ratio of the additive A to the additive B is 1:1 to 1:200, the additive A is 0.01% to 2%, and the additive B is 0.1% to 10%.

4 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive B, and the additive B comprises lithium difluorophosphate, wherein based on a total weight of the electrolyte, a weight ratio of the additive A to the lithium difluorophosphate is 10:1 to 1:1, and the lithium difluorophosphate is 0.01% to 1% by weight with respect to the total weight of the electrolyte.

5 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive C,
the additive C comprises at least one of a compound represented by a formula II-A, a compound represented by a formula II-B, a compound represented by a formula II-C, or a compound represented by a formula II-D:

wherein
R 11 and R 12 each are independently selected from a substituted or unsubstituted C 1-10 alkyl group, a substituted or unsubstituted C 2-10 alkenyl group, a substituted or unsubstituted C 6-10 aryl group, or a substituted or unsubstituted C 1-6 heterocyclic group, wherein when substitution is performed, a substituent group is one or more of a halogen, a nitro group, a cyano group, or a carboxyl group, and a heteroatom of the heterocyclic group is selected from at least one of O, N, P, and S,
R 13 is selected from a substituted or unsubstituted C 1-4 alkylidene group, a substituted or unsubstituted C 2-4 alkenylene group, or a substituted and unsubstituted C 1-6 linear alkane comprising 1 to 5 heteroatoms, wherein when substitution is performed, a substituent group is selected from an oxy group, a halogen, a C 1-3 alkyl group, or a C 2-4 alkenyl group, and the heteroatom is selected from O, N, P or S,
R 14 and R 15 each are independently selected from O, a substituted or unsubstituted C 1-4 alkylidene group, a substituted or unsubstituted C 2-4 alkenylene group, or a substituted and unsubstituted C 1-6 linear alkane comprising 1 to 5 heteroatoms, wherein being substituted means that substitution is performed with one or more substituent groups selected from a halogen, a C 1-3 alkyl group, or a C 2-4 alkenyl group, and the heteroatom is selected from O, N, P or S, and
R 16 and R 17 each are independently selected from a substituted or unsubstituted C 1-4 alkyl group or a substituted or unsubstituted C 2-4 alkenyl group; or R 16 and R 17 are connected together to form a saturated/unsaturated and substituted/unsubstituted ring comprising 3 to 6 carbons, wherein being substituted means that substitution is performed with one or more substituent groups selected from a halogen, a C 1-3 alkyl group, or a C 2-4 alkenyl group; and
the additive C is 0.1% to 10% by weight with respect to the total weight of the electrolyte.

6 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive D; and
the additive D comprises at least one of a compound represented by a formula III-A, a compound represented by a formula III-B, a compound represented by a formula III-C, or a compound represented by a formula III-D:

wherein
R 2 is selected from a C 2-10 alkenylene group, a C 6-12 cycloalkylidene group, a C 6-12 arylene group, —R 0 —C 6-12 arylene-R—, —R 0 —S—R—, or —R 0 —(O—R) n —,
R 31 , R 32 , and R 33 each are independently selected from a single bond, a C 1-6 alkylidene group, —R 0 —(O—R) n —, or —O—R—,
R 4 is selected from a C 1-10 alkylidene group, a C 2-10 alkenylene group, a C 6-12 cycloalkylidene group, a C 6-12 arylene group, —R 0 —S—R—, or —R 0 —(O—R) n —,
R 5 is selected from a C 6-12 trivalent cycloalkyl group or a C 6-12 trivalent aryl group, wherein the C 6-12 trivalent cycloalkyl group or C 6-12 trivalent aryl group is arbitrarily substituted with 1 to 3 substituent groups selected from a halogen,
R 0 and R each are independently a C 1-4 alkylidene group, and
R 2 , R 4 , R 0 , and R each are unsubstituted or substituted with one or more substituent groups selected from a halogen, wherein
n is a natural number from 0 to 3; and
the additive D is 0.1% to 12% by weight with respect to the total weight of the electrolyte.

7 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive C and the additive D;
the additive C comprises at least one of

 and
the additive D comprises
at least one of

8 . The electrolyte according to claim 1 , wherein the electrolyte comprises the additive E; and the silicon-containing carbonate compound comprises at least one of a compound represented by a formula IV-A or a compound represented by a formula IV-B:

wherein R 61 and R 62 each are independently selected from R a ,

 and at least one of R 61 and R 62 comprises Si,
R a , Rx, Ry, and Rz each are independently selected from H, a substituted or unsubstituted C 1-10 alkyl group, a substituted or unsubstituted C 2-10 alkenyl group, a substituted or unsubstituted C 6-10 cycloalkyl group, or a substituted or unsubstituted C 6-10 aryl group, wherein being substituted means that substitution is performed with one or more halogens atoms,
R′ is selected from a substituted or unsubstituted C 1-12 alkylidene group or a substituted or unsubstituted C 2-12 alkenylene group, wherein being substituted means that substitution is performed with one or more halogen atoms,
R 7 is

 wherein R b is selected from H, a halogen, a substituted or unsubstituted C 1-6 alkyl group, or a substituted or unsubstituted C 2-6 alkenyl group, wherein being substituted means that substitution is performed with one or more halogens,
Y is selected from a single bond, a substituted or unsubstituted C 1-4 alkylidene group, or a substituted or

Assignees

• Ningde Amperex Technology Ltd

Inventors

• Xu Chunrui
• Xu Yanyan
• Zheng Jianming
• Tang Chao

Classifications

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title