Method for recycling lithium salts from batteries

Patent metadata

Field	Value
Publication number	US-2024186605-A1
Application number	US-202218285094-A
Country	US
Kind code	A1
Filing date	Mar 11, 2022
Priority date	Mar 31, 2021
Publication date	Jun 6, 2024
Grant date	—

Abstract

The invention relates to a process for recycling lithium salts contained in the electrolyte of a used lithium battery, which involves supplying an electrolyte stream comprising at least one lithium salt, at least one electrolyte solvent and water; at least one step of extracting the at least one lithium salt by adding a first solvent to the electrolyte stream to recover a phase comprising the at least one lithium salt on one side and a lithium salt-depleted phase on the other side.

First claim

1 . A process for recycling lithium salts contained in the electrolyte of a used lithium battery, the process comprising:
supplying an electrolyte stream comprising at least one lithium salt, at least one electrolyte solvent and water; and at least one step of extracting the at least one lithium salt by adding a first solvent to the electrolyte stream to recover a phase comprising the at least one lithium salt on one side and a lithium salt-depleted aqueous phase on the other side.

2 . The process as claimed in claim 1 , in which, after adding the first solvent, the phase comprising the first solvent, the electrolyte solvent and the at least one lithium salt is recovered on one side and a lithium salt-depleted aqueous phase is recovered on the other side.

3 . The process as claimed in claim 1 , in which the at least one lithium salt is chosen from lithium bis(fluorosulfonyl)imide, lithium 2-trifluoromethyl-4,5-dicyanoimidazolate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluoroborate, lithium difluorophosphate and mixtures thereof.

4 . The process as claimed in claim 1 , in which the at least one lithium salt is lithium bis(fluorosulfonyl)imide.

5 . The process as claimed in claim 1 , in which the electrolyte solvent is chosen from carbonates, ethers, esters, ketones, alcohols, nitriles, amides, sulfamides and sulfonamides, and mixtures thereof.

6 . The process as claimed in claim 1 , in which the first solvent is chosen from esters, nitriles, ethers, carbonates, carbamates and mixtures thereof.

7 . The process as claimed in claim 1 , in which a second solvent is added during the extraction process.

8 . The process as claimed in claim 1 , comprising at least one additional extraction step by adding a second solvent to the phase comprising the at least one lithium salt.

9 . The process as claimed in claim 1 , comprising a step of adding a third solvent to the phase comprising the at least one lithium salt to form a mixture and an evaporation step to precipitate the at least one lithium salt.

10 . The process as claimed in claim 1 , comprising a step of evaporating the phase comprising the at least one lithium salt followed by a step of adding a third solvent to precipitate the at least one lithium salt.

11 . The process as claimed in claim 9 , in which the third solvent is chosen from alkanes, alkenes, aromatics, chlorinated compounds and mixtures thereof.

12 . The process as claimed in claim 1 , in which the stream comprising at least one lithium salt, at least one electrolyte solvent and water is obtained by placing water in contact with a used lithium battery or a portion thereof.

13 . The process as claimed in claim 1 , comprising the dissolution of the at least one recycled lithium salt in an additional electrolyte solvent.

14 . The process as claimed in claim 1 , in which the at least one lithium salt is chosen from lithium bis(fluorosulfonyl)imide, lithium 2-trifluoromethyl-4,5-dicyanoimidazolate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluoroborate, and mixtures thereof.

15 . The process as claimed in claim 7 , wherein the second solvent is chosen from alkanes, aromatic solvents, chlorinated solvents and mixtures thereof.

16 . The process as claimed in claim 8 , wherein the second solvent is chosen from alkanes, aromatic solvents, chlorinated solvents and mixtures thereof.

Assignees

• Arkema France

Inventors

• Schmidt Gregory

Classifications

• H01M10/54 Primary

  Reclaiming serviceable parts of waste accumulators · CPC title

• C22B3/40

  Mixtures · CPC title

• C22B26/12

  Obtaining lithium · CPC title

• Y02W30/84

  Recycling of batteries or fuel cells · CPC title

• C22B3/16

  in organic solutions · CPC title