Method for recovering lithium precursor from lithium secondary battery

Patent metadata

Field	Value
Publication number	US-2024150191-A1
Application number	US-202218549348-A
Country	US
Kind code	A1
Filing date	Mar 3, 2022
Priority date	Mar 8, 2021
Publication date	May 9, 2024
Grant date	—

Abstract

In a method for recovering lithium hydroxide from a lithium secondary battery, cathode powder is prepared from a cathode of the lithium secondary battery. A cathode active material mixture is prepared by mixing the cathode powder with a calcium compound. The cathode active material mixture is reduced to form a preliminary precursor mixture. A lithium precursor is recovered from the preliminary precursor mixture. Therefore, a lithium precursor can be obtained with high purity without a complicated leaching process or an additional process, which result from a wet-based acid solution process.

First claim

What is claimed is:

1 . A method for recovering a lithium precursor from a lithium secondary battery, the method comprising:
preparing cathode powder from a cathode of the lithium secondary battery; preparing a cathode active material mixture by mixing the cathode powder with a calcium compound; reducing the cathode active material mixture to form a preliminary precursor mixture; and recovering a lithium precursor from the preliminary precursor mixture.

2 . The method according to claim 1 , wherein the cathode comprises a waste cathode derived from scrap.

3 . The method according to claim 1 , wherein the step of preparing the cathode powder comprises dry pulverizing the cathode of the lithium secondary battery.

4 . The method according to claim 1 , wherein the cathode comprises a current collector and a cathode active material layer formed on the current collector and including a binder and a cathode active material, and
the cathode powder comprises components derived from the cathode active material and the binder.

5 . The method according to claim 4 , wherein the step of preparing the cathode active material mixture or the step of forming the preliminary precursor mixture comprises reacting a component derived from the binder with the calcium compound to at least partially remove the component.

6 . The method according to claim 5 , wherein the component derived from the binder comprises a fluorine component and a carbon component.

7 . The method according to claim 5 , wherein the calcium compound includes calcium oxide.

8 . The method according to claim 1 , wherein reacting the calcium compound with the cathode powder comprises mixing the cathode powder with a calcium compound containing 0.5 to 1.5 times more calcium element than fluorine element contained in the cathode powder.

9 . The method according to claim 8 , wherein the step of preparing the cathode active material mixture comprises performing heat treatment on the cathode powder and the calcium compound together at a temperature of 300 to 600° C.

10 . The method according to claim 1 , wherein the reduction treatment comprises dry reduction using a hydrogen gas or a carbon-based material.

11 . The method according to claim 1 , wherein the reduction treatment temperature is 400 to 600° C.

12 . The method according to claim 1 , wherein the step of recovering the lithium precursor from the preliminary precursor mixture comprises obtaining a lithium precursor hydrate by washing the preliminary precursor mixture with water.

13 . The method according to claim 12 , wherein a selectivity of lithium hydroxide in the lithium precursor hydrate is 97% or more.

Assignees

• Sk Innovation Co Ltd

Inventors

• Seo Young Bin
• Park Ji Yun
• Son Sung Real
• Lee Sang Ick
• Hong Suk Joon
• Kim Ji Min

Classifications

• C01D15/02 Primary

  Oxides; Hydroxides · CPC title

• C01D15/04

  Halides · CPC title

• C01D15/08

  Carbonates; Bicarbonates · CPC title

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title

• C22B7/00 Primary

  Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; {Methods of a general interest or applied to the winning of more than two metals (briquetting of scrap C22B1/248; preliminary treatment of scrap C22B1/005)} · CPC title