Method for producing lithium secondary battery thick film and method for producing lithium secondary battery by using electrostatic slurry spraying of slurry containing sulfide-based solid electrolyte

Patent metadata

Field	Value
Publication number	US-11316141-B2
Application number	US-201716319672-A
Country	US
Kind code	B2
Filing date	Jul 19, 2017
Priority date	Jul 19, 2016
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

Provided are a method for producing a lithium secondary battery thick film and a method for producing a lithium secondary battery, by using electrostatic slurry spraying of slurry containing a sulfide-based solid electrolyte. Particularly, the method for producing a lithium secondary battery thick film comprises: a step of preparing slurry in which the powder of a sulfide-based solid electrolyte is mixed with at least one solvent selected between a dichloroethane and a dichlorobenzene, at the weight ratio of 1:10 to 1:100; and a step of depositing a lithium secondary battery thick film by electrostatically spraying the slurry on a current collector under a nitrogen atmosphere in the cone-jet mode.

First claim

The invention claimed is:

1. A method of forming a lithium secondary battery thick film by electrostatically spraying a slurry including a sulfide-based solid electrolyte, the method comprising:
preparing a slurry in which a powder of a sulfide-based solid electrolyte is mixed into at least one solvent selected from dichloroethane and dichlorobenzene at a weight ratio of 1:10 to 1:100; and
electrostatically spraying the slurry on a current collector in a cone jet mode in a nitrogen atmosphere to deposit a lithium secondary battery thick film.

2. The method of claim 1 , wherein the sulfide-based solid electrolyte includes a compound of sulfur and at least two components selected from among lithium, phosphorus, boron, silicon, and aluminum.

3. The method of claim 1 , wherein, in the preparing of the slurry, at least one binder selected from among nitrile butadiene rubber (NBR), polyvinylpyrrolidone (PVP), and polyvinylidene fluoride (PVDF) is further mixed into the solvent.

4. The method of claim 1 , wherein, in the preparing of the slurry, a powder of an active material and a powder of a conductive material are further mixed into the solvent, and
the lithium secondary battery thick film is a composite electrode thick film in which the sulfide-based solid electrolyte, the active material, and the conductive material are mixed.

5. The method of claim 1 , wherein the deposition of the lithium secondary battery thick film includes heating the current collector during the electrostatic spraying of the slurry.

6. The method of claim 1 , wherein a ratio of an applied voltage to a spray distance to the current collector is in a range of 1.0 kV/cm to 1.5 kV/cm.

7. The method of claim 1 , wherein a spray flow velocity of the slurry is in a range of 115 cm/h to 320 cm/h during the electrostatic spraying.

8. A method of manufacturing a lithium secondary battery, the method comprising:
electrostatically spraying a first composite electrode slurry including a powder of a sulfide-based solid electrolyte, a powder of a first active material, and a powder of a conductive material to deposit a first lithium secondary battery composite electrode thick film;
electrostatically spraying a solid electrolyte slurry including a powder of a sulfide-based solid electrolyte on the first lithium secondary battery composite electrode thick film to deposit a lithium secondary battery solid electrolyte thick film; and
electrostatically spraying a second composite electrode slurry including a powder of a sulfide-based solid electrolyte, a powder of a second active material, and a powder of a conductive material on the lithium secondary battery solid electrolyte thick film to deposit a second lithium secondary battery composite electrode thick film,
wherein one of the first active material and the second active material is a positive active material and the other is a negative active material, and
the first composite electrode slurry, the solid electrolyte slurry, and the second composite electrode slurry each include at least one solvent selected from dichloroethane and dichlorobenzene and are electrostatically sprayed in a cone-jet mode in a nitrogen atmosphere.

Assignees

• Univ Hanyang Ind Univ Coop Found

Inventors

• Shin Dong Wook
• Park Chan Hwi
• Lee Se Wook

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M2300/0068

  inorganic · CPC title

• H01M4/623

  fluorinated polymers · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title