Nickel-rich battery recycling
A battery recycling process recovers lithium from nickel-rich cathode material in a recycling stream of end-of-life batteries. A dilute acid leach of a high nickel content cathode material contains a mixture of sulfuric acid based on a molar quantity of lithium in the cathode material. The highly selective leach generates a lithium rich solution with a small amount of nickel removable by nanofiltration to achieve a highly efficient recovery of the lithium contained in the recycling stream. A quantity of the leach acid based on the lithium content and a quantity of water based on a total black mass of the recycling stream results in a highly selective, near pure lithium leach when the recycling stream results from high nickel NMC batteries such as 811.
1. A method for recycling lithium from batteries, comprising:
combining a quantity of leach acid and a quantity of a granular mass of a charge material from a battery recycling stream, the granular mass comprising at least 80 mol % nickel and the quantity of leach acid based on a molar quantity of lithium in the granular mass;
heating the combined granular mass and leach acid; and
recovering lithium from the granular mass, the recovered lithium comprising less than 10% nickel.
2. The method of claim 1 , wherein the granular mass of charge material comprises a cathode material having at least 80 mol % nickel of cathode material metals in the granular mass.
3. The method of claim 1 wherein the quantity of the leach acid is based on achieving a molar ratio of 0.4-0.7 of the leach acid to Li in the granular mass of charge material.
4. The method of claim 1 wherein the granular mass of the charge material is received from a recycling stream of batteries having a lithium-based charge material.
5. The method of claim 1 wherein the molar ratio of the leach acid to Li in the granular mass is 0.045-0.6.
6. The method of claim 1 wherein the combined granular mass and leach acid is heated to 60-100° C.
7. The method of claim 1 wherein the leach acid is sulfuric acid.
8. The method of claim 1 wherein the lithium recovered from the granular mass comprises between 3%-10% nickel.
9. The method of claim 1 further comprising agitating waste batteries for generating a comingled mass of charge material, current collectors and casing; and
separating the charge material in a granular form.
10. The method of claim 1 further comprising:
sourcing the granular mass of charge material from a recycling stream including batteries based on an NMC 811 chemistry.
11. The method of claim 1 wherein the leach agent includes acids selected from the group consisting of sulfuric, hydrochloric, acetic, nitric, formic, oxalic and boric.
12. A method for recycling lithium from high nickel lithium batteries, comprising:
agitating a recycling stream of end-of-life lithium batteries to generate a black mass of high nickel cathode materials including cathode material of at least 80% nickel of cathode material metals in the granular mass;
determining a quantity of a leaching acid based on a molar quantity of lithium in the black mass for achieving a molar ratio in a range between 0.4-0.70 of leach acid to Li in the black mass;
adding the determined quantity of leaching acid to the black mass to form a leach mixture;
mixing and heating the leach mixture between 60°-80° C. for 1-6 hours;
filtering the leach mixture with a 1 micron filter membrane for removing undissolved materials;
removing dissolved nickel from the leach mixture via nanofiltration to yield a lithium sulfate solution including dissolved Li from the black mass;
concentrating the lithium sulfate via reverse osmosis and evaporation to a crystalline form of recovered lithium such that the recovered lithium comprises less than 10% nickel.
13. The method of claim 12 wherein the leach acid is sulfuric acid.
14. The method of claim 12 , wherein the molar ratio is in a range of between 0.45-0.6.