Method for recovering active metal of lithium secondary battery

Patent metadata

Field	Value
Publication number	US-2023108786-A1
Application number	US-202117907816-A
Country	US
Kind code	A1
Filing date	Feb 23, 2021
Priority date	Feb 27, 2020
Publication date	Apr 6, 2023
Grant date	—

Abstract

In a method for recovering an active metal of a lithium secondary battery, a cathode active material mixture is prepared from a cathode of a lithium secondary battery. A first reductive process using a first reductive reaction gas and a second reductive process using a second reductive reaction gas that has a higher reaction source concentration than that of the first reductive reaction gas are performed sequentially and continuously to convert the cathode active material mixture into a preliminary precursor mixture. A lithium precursor is recovered from the preliminary precursor mixture. A lithium recovery ratio may be increased by a stepwise reduction while preventing an increase of heating value.

First claim

1 . A method for recovering an active metal of a lithium secondary battery, the method comprising:
preparing a cathode active material mixture from a cathode of a lithium secondary battery; sequentially and continuously performing a first reductive process using a first reductive reaction gas and a second reductive process using a second reductive reaction gas that has a higher reaction source concentration than that of the first reductive reaction gas to convert the cathode active material mixture into a preliminary precursor mixture; and recovering a lithium precursor from the preliminary precursor mixture.

2 . The method for recovering an active metal of a lithium secondary battery of claim 1 , wherein the first reductive reaction gas and the second reductive reaction gas comprise hydrogen, and
a hydrogen concentration of the first reductive reaction gas is smaller than a hydrogen concentration of the second reductive reaction gas.

3 . The method for recovering an active metal of a lithium secondary battery of claim 2 , wherein the hydrogen concentration of the first reductive reaction gas is in a range from 5 to 15 volume %, and the hydrogen concentration of the second reductive reaction gas is 20 volume % or more.

4 . The method for recovering an active metal of a lithium secondary battery of claim 2 , wherein the hydrogen concentration of the first reductive reaction gas is in a range from 5 to 10 volume %, and the hydrogen concentration of the second reductive reaction gas is in a range from 20 to 40 volume %.

5 . The method for recovering an active metal of a lithium secondary battery of claim 1 , wherein a reaction temperature of the second reductive process is higher than a reaction temperature of the first reductive process.

6 . The method for recovering an active metal of a lithium secondary battery of claim 5 , wherein the reaction temperature of the first reductive process is in a range from 300 to 450° C., and the reaction temperature of the second reductive process is in a range from 460 to 800° C.

7 . The method for recovering an active metal of a lithium secondary battery of claim 1 , wherein the first reductive process and the second reductive process comprise supplying the first reductive reaction gas and the second reductive reaction gas, respectively, into a fluidized bed reactor.

8 . The method for recovering an active metal of a lithium secondary battery of claim 1 , wherein the preliminary precursor mixture comprises preliminary lithium precursor particles and transition metal-containing particles.

9 . The method for recovering an active metal of a lithium secondary battery of claim 8 , wherein the preliminary lithium precursor particles comprise at least one of lithium hydroxide, lithium oxide and lithium carbonate.

10 . The method for recovering an active metal of a lithium secondary battery of claim 8 , wherein the recovering the lithium precursor comprises washing the preliminary lithium precursor particles with water.

11 . The method for recovering an active metal of a lithium secondary battery of claim 8 , wherein the transition metal-containing particles comprise nickel, cobalt, manganese or an oxide thereof.

12 . The method for recovering an active metal of a lithium secondary battery of claim 11 , further comprising selectively treating the transition metal-containing particles with an acid solution to recover a transition metal precursor in a form of an acid salt.

Assignees

• Sk Innovation Co Ltd

Inventors

• Hong Suk Joon
• Ha Hyeon Bae
• Kim Ji Min
• Sung Min Ji
• Son Sung Real

Classifications

• Y02P10/20

  Recycling · CPC title

• C01G53/04

  Oxides · CPC title

• C01G51/10

  Sulfates · CPC title

• C22B5/12

  by gases · CPC title

• C01D15/08

  Carbonates; Bicarbonates · CPC title