Thermally responsive electrolytes

Patent metadata

Field	Value
Publication number	US-10693188-B2
Application number	US-201514926213-A
Country	US
Kind code	B2
Filing date	Oct 29, 2015
Priority date	Oct 30, 2014
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

Methods compositions for controlling lithium-ion cell performance, using thermally responsive electrolytes incorporating compounds that exhibit a phase transition at elevated temperatures and are suited for incorporation into lithium-ion and lithium-metal cells are disclosed.

First claim

We claim:

1. A method comprising:
providing a lithium-ion cell, said cell comprising a thermally responsive electrolyte in an initial single phase solution, said thermally responsive electrolyte comprising:
a thermally responsive polymer,
a thermally stable ionic liquid; and
a lithium salt;

separating the thermally responsive electrolyte into the biphasic mixture phase at temperatures ranging from about 50° C. to about 160° C.;
decreasing conductivity of the thermally responsive electrolyte in the biphasic mixture phase;
inhibiting lithium-ion cell operation when the lithium-ion cell is in the biphasic mixture phase;
reversing the thermally responsive electrolyte from the biphasic mixture at a temperature below about 50° C.;
wherein the thermally responsive electrolyte in the biphasic mixture phase has a conductivity that is less than the conductivity of the thermally responsive electrolyte in the initial single phase when the temperature of the thermally responsive electrolyte is in the temperature range of from about 50° C. to about 160° C.; and
wherein the thermally responsive electrolyte is configured to exhibit a reversible phase transition from the biphasic mixture phase to the initial single phase at a temperature below about 50° C.

2. The method of claim 1 , wherein the thermally responsive electrolyte comprises a thermally responsive polymer selected from the group consisting of: poly(ethylene oxide) and other polyether derivatives; poly(aryl methacrylates), poly(alkyl methacrylates) and other poly(methacrylate) derivatives, poly(ionic liquids), copolymers or cross-linked polymers therein, and combinations thereof.

3. The method of claim 1 , wherein thermally responsive electrolyte further comprises an ionic liquid, the ionic liquid selected from the group consisting of: imidazolium-, pyrrolidinium-, pyridinium-, phosphonium-, ammonium-, and sulfonium-based ionic liquids, and combinations thereof.

4. The method of claim 1 , wherein the thermally responsive electrolyte further comprises a lithium salt, said lithium salt selected from the group consisting of: lithium tetrafluoroborate, lithium hexafluoroborate, lithium bis(trifluoromethanesulfonyl)imide, lithium perchlorate, and combinations thereof.

5. The method of claim 1 , wherein the thermally responsive electrolyte in the biphasic mixture inhibits conductivity within the lithium-ion cell when the temperature of the electrolyte is in the range of from about 50° C. to about 160° C.

6. The method of claim 1 , wherein the thermally responsive electrolyte in the biphasic mixture inhibits ion transport in the electrolyte.

7. The method of claim 1 , wherein the thermally responsive electrolyte inhibits charge-transfer or ion intercalation when the temperature of the electrolyte is in the range of from about 50° C. to about 160° C.

8. A lithium-ion cell comprising:
a thermally responsive electrolyte, the thermally responsive electrolyte comprising:
a thermally responsive polymer;
a thermally stable solvent; and
a lithium salt;

wherein, the thermally responsive electrolyte is configured to transition from an initial single phase to a biphasic mixture phase at a temperature of from about 50° C. to about 160° C.;
wherein thermally responsive electrolyte is configured to inhibit lithium ion cell thermal failure by interrupting lithium ion operation when the thermally responsive electrolyte is in the biphasic mixture phase;
wherein the thermally responsive electrolyte in the biphasic mixture phase has a conductivity that is less than the conductivity of the thermally responsive electrolyte in the initial single phase when the temperature of the thermally responsive electrolyte is in the temperature range of from about 50° C. to about 160° C.; and
wherein the thermally responsive electrolyte is configured to transition from the biphasic mixture phase to the initial single phase at a temperature below about 50° C.

9. The lithium-ion cell of claim 8 , wherein the thermally responsive polymer is selected from the group consisting of: poly(ethylene oxide) and other polyether derivatives;
poly(aryl methacrylates), poly(alkyl methacrylates), and other poly(methacrylate) derivatives, poly(ionic liquids), copolymers or cross-linked polymers therein, and combinations thereof.

10. The lithium-ion cell of claim 9 , wherein the thermally responsive polymer has an average molecular weight of from about 1000 to about 1,000,000.

11. The lithium-ion cell of claim 8 , wherein the solvent is an ionic liquid selected from the group consisting of: imidazolium-, pyrrolidinium-, pyridinium-, phosphonium-, ammonium-, and sulfonium-based ionic liquids, and combinations thereof.

12. The lithium-ion cell of claim 8 , wherein the lithium salt is selected from the group consisting of: lithium tetrafluoroborate, lithium hexafluoroborate, lithium bis(trifluoromethanesulfonyl)imide, lithium perchlorate, and combinations thereof.

13. A component comprising the lithium-ion cell of claim 8 .

14. A vehicle comprising the lithium-ion cell of claim 8 .

15. A thermally responsive electrolyte comprising:
a thermally responsive polymer;
a thermally stable solvent;
a lithium salt;
wherein, the thermally responsive electrolyte is configured to transition from an initial single phase to a biphasic mixture phase at a temperature ranging from about 50° C. to about 160° C.;
wherein thermally responsive electrolyte is configured to inhibit lithium ion cell thermal failure by interrupting lithium ion cell operation when the thermally responsive electrolyte is in the biphasic mixture phase;
wherein the thermally responsive electrolyte in the biphasic mixture phase has a conductivity that is less than the conductivity of the thermally responsive electrolyte in the initial single phase when the temperature of the thermally responsive electrolyte is in the temperature range of from about 50° C. to about 160° C.; and
wherein the thermally responsive electrolyte is configured to transition from the biphasic mixture phase to the initial single phase at a temperature below about 50° C.

16. The thermally responsive electrolyte of claim 15 , wherein the thermally responsive polymer is selected from the group consisting of: poly(ethylene oxide) and other polyether derivatives; poly(aryl methacrylates), poly(alkyl methacrylates), and other poly(methacrylate) derivatives, poly(ionic liquids), copolymers or cross-linked polymers therein, and combinations thereof.

17. The thermally responsive electrolyte of claim 15 , wherein the thermally responsive polymer has an average molecular weight of from about 1000 to about 1,000,000.

18. The thermally responsive electrolyte of claim 15 , wherein the solvent is an ionic liquid selected from the group consisting of: imidazolium, pyrrolidinium, pyridinium, phosphonium, ammonium, sulfonium-based ionic liquids, and combinations thereof.

19. The thermally responsive electrolyte of claim 15 , wherein the lithium salt is selected from the group consisting of: lithium tetrafluoroborate, lithium hexafluoroborate, lithium bis(trifluoromethanesulfonyl)imide, lithium perchlorate, and combinations thereof.

20. The thermally responsive electrolyte of claim 16 , wherein the thermally responsive polymer exhibits a predetermined phase transition at a temperature of from about 50° C. to about 160° C.

21. A component comprising the thermally responsive electrolyte of claim 15 .

22. An energy storage component comprising the thermally re

Assignees

• Univ Clemson

Inventors

• Roberts Mark E
• Kelly Jesse C

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2300/0028

  characterised by the solvent · CPC title

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M10/0564 Primary

  the electrolyte being constituted of organic materials only · CPC title

• H01M10/0568

  characterised by the solutes · CPC title