Method for separating transition metal from waste positive electrode material

Patent metadata

Field	Value
Publication number	US-12266771-B2
Application number	US-202017608904-A
Country	US
Kind code	B2
Filing date	Dec 15, 2020
Priority date	Dec 16, 2019
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

A method for separating a transition metal from a waste positive electrode material includes step 1 of preparing a waste positive electrode material represented by Formula 1, step 2 of heat treating the waste positive electrode material in an inert gas atmosphere or an oxygen atmosphere to phase separate the waste positive electrode material into a lithium oxide and a metal oxide, step 3 of cooling an obtained product of step 2 to room temperature in an inert atmosphere, and step 4 of mixing a cooled product cooled to room temperature in step 3 with distilled water, and then filtering the mixture to leach a transition metal.

First claim

The invention claimed is:

1. A method for separating a transition metal from a waste positive electrode material, the method comprising:
step 1 of preparing a waste positive electrode material represented by Formula 1 below;
step 2 of heat treating the waste positive electrode material in an inert gas atmosphere or an oxygen atmosphere to phase separate the waste positive electrode material into a lithium oxide and a metal oxide to form an obtained product;
step 3 of cooling the obtained product of the step 2 to room temperature in an inert atmosphere to form a cooled product; and
step 4 of mixing the cooled product cooled to room temperature in the step 3 with distilled water to form a mixture, and then filtering the mixture to leach a transition metal:
Li 1+a Ni 1−x M x O 2   [Formula 1]

wherein in Formula 1 above,
M is one or more selected from the group consisting of Co, Mn, and Al, and 0≤a≤0.3, and 0≤x≤0.5.

2. The method of claim 1 , wherein in the step 2, the heat treating is performed at 900° C. or higher in an oxygen atmosphere.

3. The method of claim 2 , wherein the heat treating is performed at 900°° C. to 1,000° C. in the oxygen atmosphere.

4. The method of claim 1 , wherein in the step 2, the heat treating is performed at 800° C. or higher in an inert gas atmosphere.

5. The method of claim 4 , wherein the heat treating is performed at 800° C. to 950°° C. in the inert gas atmosphere.

6. The method of claim 4 , wherein the inert gas atmosphere of the step 2further contains hydrogen gas in an amount of 10 vol % or less based on 100 vol % of an inert gas.

7. The method of claim 1 , wherein the waste positive electrode material of the step 1 contains nickel in 80 mol % or greater based on a total number of moles of transition metals except for lithium.

8. The method of claim 1 , wherein during the cooling of the step 3, a temperature lowering rate is 1° C./min to 10° C./min.

9. The method of claim 1 , wherein in the step 4, the cooled product and the distilled water are mixed at 1:0.3 to 1:2.

10. The method of claim 1 , wherein the transition metal leached in the step 4 is in the form of a lithium compound including a lithium hydroxide formed by a reaction of the lithium oxide and the distilled water.

11. The method of claim 1 , wherein the transition metal leached in the step 4 is in the form of a nickel metal oxide including nickel and M, wherein the M is one or more selected from the group consisting of Co, Mn, and Al.

12. The method of claim 1 , wherein the step 1 to the step 4 are repeatedly performed once to 4 times.

13. The method of claim 1 , wherein when the size of a unit cell obtained by measuring the transition metal separated in Step 4 by XRD is 0.42 nm to 0.4165 nm, the transition metal is determined to have purity of 80% or greater.

Assignees

• Lg Chemical Ltd

Inventors

• Jung Won Sig
• Rhee Tae Young
• Choi Hwan Young

Classifications

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01D15/02 Primary

  Oxides; Hydroxides · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• C22B7/001

  Dry processes · CPC title