Method for recovering waste lithium cobalt oxide battery

Patent metadata

Field	Value
Publication number	US-2024274913-A1
Application number	US-202218559058-A
Country	US
Kind code	A1
Filing date	Aug 24, 2022
Priority date	Nov 30, 2021
Publication date	Aug 15, 2024
Grant date	—

Abstract

Disclosed is a method for recovering a waste lithium cobalt oxide battery, the method comprising: feeding a lithium cobalt oxide battery black powder in a column-shaped container, adding a first acid to the column-shaped container for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a first leachate and leaching residues, wherein the first acid is a weak acid, and a filtering structure is arranged at the bottom of the column-shaped container; and adding a second acid to the column-shaped container containing the leaching residues for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a second leachate and graphite, wherein the second acid is a strong acid. According to the present invention, consumption of an inorganic strong acid can be reduced, emission of strong acid gas is reduced, and green and low-carbon heat leaching of the black powder is achieved.

First claim

1 . A method for recycling a spent lithium cobalt oxide battery, comprising the following steps:
S1: putting black powders from a lithium cobalt oxide battery into a column-shaped container, adding a first acid to the column-shaped container for hot leaching until solids in the column-shaped container no longer decrease, to obtain a first leachate and a leaching residue, wherein the first acid is selected from the group consisting of methanoic acid, acetic acid, benzoic acid and a mixture thereof, and the concentration of the first acid is 0.1-35 wt %; the bottom of the column-shaped container is provided with a filter structure; the first acid has a temperature of 35-80° C., and the first acid further contains sodium thiosulfate in an amount of 0.1-12 wt %; and S2: adding a second acid to the column-shaped container containing the leaching residue for hot leaching until solids in the column-shaped container no longer decrease, to obtain a second leachate and graphite, wherein the second acid is a strong acid.

2 . The method according to claim 1 , wherein in S1, the black powders from a lithium cobalt oxide battery is obtained by: disassembling the spent lithium cobalt oxide battery to obtain cells, measuring the voltage of the cells to classify the cells into low-voltage cells and high-voltage cells, discharging, pyrolyzing and crushing the low-voltage cells, and removing copper-aluminum foils and separators to obtain the black powders from a lithium cobalt oxide battery.

3 . The method according to claim 2 , wherein the high-voltage cells are assembled into a battery pack to provide power for heating.

4 . The method according to claim 1 , further comprising a step of producing cobalt oxalate from the first leachate by
adding alkali to the first leachate to adjust pH and separating aluminium hydroxide precipitations; adding the second acid to adjust pH to 3.0-4.5, adding a synergistic extractant for extraction and separating a cobalt-containing phase; adding the second acid to the cobalt-containing phase for back-extraction and separating an aqueous phase by back-extraction; and adding a compound containing oxalate to the aqueous phase from the back-extraction and obtaining a cobalt oxalate by solid-liquid separation.

5 . The method according to claim 1 , wherein in S2, to the second leachate, adding aluminum powders to separate out copper sponge, and adding alkali to adjust pH to 4.0-6.5, and separating out aluminium hydroxide.

6 . (canceled)

7 . (canceled)

8 . The method according to claim 1 , wherein in S2, the second acid is selected from the group consisting of hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid and a mixture thereof; the concentration of the second acid is 0.01-0.2 mol/L; and the second acid has a temperature of 35-80° C.

9 . The method according to claim 4 , wherein the synergistic extractant consists of extractant and cyclohexane at a mass ratio of (15-50):(30-85), wherein the extractant consists of dialkyl hypophosphorous acid and mono-2-ethylhexyl (2-ethylhexyl)phosphonate at a volume ratio of (1-4):(1-10).

10 . The method according to claim 4 , wherein the compound containing oxalate is selected from the group consisting of oxalic acid, ammonium oxalate, sodium oxalate and a mixture thereof.

Assignees

• Guangdong Brunp Recycling Technology Co Ltd
• Hunan Brunp Recycling Tech Co Ltd
• Yichang Brunp Contemporary Amperex Co Ltd

Inventors

• Zhong Yingsheng
• Yu Haijun
• Xie Yinghao
• Li Aixia
• Li Bo
• Li Changdong

Classifications

• Y02W30/84

  Recycling of batteries or fuel cells · CPC title

• Y02P10/20

  Recycling · CPC title

• C22B26/12

  Obtaining lithium · 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

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title