Method for purifying aqueous sulfonylimide solution, method for producing non-aqueous electrolyte, and method for producing electrolyte composition

Patent metadata

Field	Value
Publication number	US-2025070254-A1
Application number	US-202218575302-A
Country	US
Kind code	A1
Filing date	Jun 6, 2022
Priority date	Jun 30, 2021
Publication date	Feb 27, 2025
Grant date	—

Abstract

A method for purifying an aqueous sulfonylimide solution includes heating an aqueous sulfonylimide solution containing a sulfonylimide compound represented by the general formula (1). A method for producing a non-aqueous electrolyte solution includes adding an electrolyte solution solvent to the aqueous sulfonylimide solution purified by the purification method to dehydrate the aqueous sulfonylimide solution. A method for producing an electrolyte composition includes distilling off the electrolyte solution solvent from the non-aqueous electrolyte solution obtained by the production method.

First claim

1 . A method for purifying an aqueous sulfonylimide solution, the method comprising:
heating an aqueous sulfonylimide solution containing a sulfonylimide compound represented by the general formula (1): LiN(RSO 2 )(FSO 2 ) (where R represents a fluorine atom, an alkyl group with 1 to 6 carbon atoms, or a fluoroalkyl group with 1 to 6 carbon atoms) (1).

2 . The method for purifying an aqueous sulfonylimide solution of claim 1 , wherein
the heating is performed at 60° C. or more and 120° C. or less.

3 . The method for purifying an aqueous sulfonylimide solution of claim 1 or 2 , wherein
the heating is performed at 30 kPa or less.

4 . The method for purifying an aqueous sulfonylimide solution of any one of claims 1 to 3 , wherein
the aqueous sulfonylimide solution after the heating contains FSO 3 Li at a concentration of 1500 ppm by mass or less with respect to the sulfonylimide compound represented by the general formula (1).

5 . A method for producing a non-aqueous electrolyte solution containing the sulfonylimide compound represented by the general formula (1) as an electrolyte and an electrolyte solution solvent, wherein
the electrolyte solution solvent is added to the aqueous sulfonylimide solution purified by the purification method of any one of claims 1 to 4 to dehydrate the aqueous sulfonylimide solution.

6 . The method for producing a non-aqueous electrolyte solution of claim 5 , wherein
the electrolyte solution solvent is a carbonate solvent.

7 . The method for producing a non-aqueous electrolyte solution of claim 5 or 6 , wherein
the non-aqueous electrolyte solution contains FSO 3 Li at a concentration of 100 ppm by mass or less with respect to the electrolyte.

8 . A method for producing an electrolyte composition containing the sulfonylimide compound represented by the general formula (1) as an electrolyte, the method comprising:
distilling off the electrolyte solution solvent from the non-aqueous electrolyte solution obtained by the production method of any one of claims 5 to 7 , wherein the electrolyte composition contains FSO 3 Li at a concentration of 100 ppm by mass or less with respect to the electrolyte.

Assignees

• Nippon Catalytic Chem Ind

Inventors

• Watabe Ryo
• Kobatake Takayuki
• OOKUBO Chie
• Arakawa Motohiro
• Takida Hiroshi

Classifications

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title