Methods for cathode recycling of end-of-life lithium batteries
Disclosed herein are improved methods and devices for recycling lithium cathodes from batteries using a Soxhlet extractor.
1. A method for recycling lithium cathode from a battery comprising contacting a lithium cathode comprising a binder with a quinone-based redox mediator wherein the method further comprises the step of a Soxhlet extraction process to remove the binder from the lithium cathode and wherein the Soxhlet extraction process comprises a condenser that is cooled to a temperature of less than negative 100° C.
2. The method of claim 1 wherein the binder is polyvinylidene fluoride (PVDF).
3. The method of claim 1 wherein the Soxhlet extraction process takes place under a vacuum.
4. The method of claim 1 wherein the binder is soluble in a solvent used in the Soxhlet extraction process.
5. The method of claim 1 further comprising mechanical agitation of the lithium cathode.
6. The method of claim 1 further comprising sonication of the lithium cathode.
7. The method of claim 1 wherein the Soxhlet extraction process comprises a condenser that is cooled to a temperature of less than negative 196° C.
8. The method of claim 1 wherein the binder is isolated from the lithium cathode.
9. The method of claim 1 wherein the redox mediator is 3,5-di-tert-butyl-o-benzoquinone.
10. The method of claim 1 wherein the redox mediator is selected from the group consisting of thymoquinone, methyl-p-benzoquinone, duroquinone, and naphthoquinone.
11. The method of claim 1 wherein the cathode is Li[NiMnCo] 1/3 O 2 .
12. The method of claim 1 wherein the cathode is Li 0.9 [NiMnCo] 1/3 O 2 .
13. The method of claim 1 wherein the redox mediator is dissolved in an electrolyte.
14. The method of claim 13 wherein the electrolyte is dimethyl ether (DME).
15. The method of claim 1 further comprising using a cathode powder that is agitated in a redox-mediator electrolyte with the Li metal covered with a porous polypropylene membrane.
16. The method of claim 15 wherein the redox mediator is a quinone-based redox mediator.
17. The method of claim 16 wherein the redox mediator is 3,5-di-tert-butyl-o-benzoquinone.
18. The method of claim 16 wherein the redox mediator is selected from the group consisting of thymoquinone, methyl-p-benzoquinone, duroquinone, and naphthoquinone.