Process for recycling electrode materials from lithium-ion batteries

1. A process for recycling electrode material from lithium-ion batteries, comprising:

1) harvesting the anode and cathode electrode materials from lithium-ion batteries, in the form of a mixed powder or slurry;

2) separating the mixed powder or slurry into anode and cathode fractions by means of dense liquid separation, comprising:

a) mixing the mixed powder or slurry in a high density liquid which has a density above 2 g/cc and below 4.5 g/cc, and whose density lies between those of the anode and cathode material, respectively;

b) after sufficient time so as to allow the anode material, low-density fraction to float to the top of the liquid mixture and the cathode material, high-density fraction to sink to the bottom of the liquid mixture, collecting the solid phases of the separated fractions; and

c) filtering and rinsing the collected solids with appropriate solvent to remove any residual high density liquid, and drying the collected solids.

2. The process according to claim 1 , wherein the anode material is graphite anode material, the cathode material is lithium metal oxide material.

3. The process according to claim 2 , wherein the high density liquid is selected from one or more of bromoform, CHBr 2 CH 2 Br, CH 2 BrCBr 3 , CHBr 2 CBr 3 , CHBr 2 CHBr 2 , and all isomers of tribromopropane, tetrabromopropane and pentabromopentane and tribromobenzene, or thallous ethoxide, and aqueous thallous formate and thallous malonate.

4. The process according to claim 1 , wherein the high density liquid is selected from one or more of bromoform, CHBr 2 CH 2 Br, CH 2 BrCBr 3 , CHBr 2 CBr 3 , CHBr 2 CHBr 2 , and all isomers of tribromopropane, tetrabromopropane and pentabromopentane and tribromobenzene, or thallous ethoxide, and aqueous thallous formate and thallous malonate.

5. The process according to claim 1 , wherein the high density liquid phase is an aqueous or non-aqueous solution containing lithium or sodium based metatungstates, polytungstates, or heteropolytungstates.

6. The process according to claim 1 , wherein the high density liquid is inert to the recovered battery materials, even when they are in a charged state.

7. The process according to claim 1 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:20.

8. The process according to claim 1 , wherein the mixed powder has a particle size of 5-500 μm.

9. The process according to claim 1 , further comprising

3) purifying and regenerating the anode and cathode fractions for reuse in new lithium-ion batteries.

10. The process according to claim 1 , wherein the separation is centrifugal separation.

11. The process according to claim 1 , which is carried out as a continuous process.

12. The process according to claim 1 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:5-1:50.

13. The process according to claim 1 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:30.

14. The process according to claim 2 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:5-1:50.

15. The process according to claim 2 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:30.

16. The process according to claim 2 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:20.

17. The process according to claim 3 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:5-1:50.

18. The process according to claim 3 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:30.

19. The process according to claim 3 , wherein the mixed powder is mixed with the high density liquid in a mass ratio of 1:10-1:20.