Method of preparing negative electrode

Patent metadata

Field	Value
Publication number	US-12315906-B2
Application number	US-202017770239-A
Country	US
Kind code	B2
Filing date	Oct 30, 2020
Priority date	Nov 1, 2019
Publication date	May 27, 2025
Grant date	May 27, 2025

Abstract

Disclosed is a method of preparing a negative electrode which includes the steps of: forming a cell by sequentially stacking a preliminary negative electrode, a separator, and a lithium metal, immersing the cell in an electrolyte solution comprising a lithium salt and a solvent; applying a current after the cell is immersed in the electrolyte solution containing the lithium salt and the solvent, separating the preliminary negative electrode from the cell after removing the cell immersed in the electrolyte solution from the electrolyte solution, washing the separated preliminary negative electrode, performing a first drying on the washed preliminary negative electrode at room temperature, and performing a second drying on the first dried preliminary negative electrode at a temperature ranging from 30° C. to 70° C. in a vacuum state.

First claim

The invention claimed is:

1. A method of preparing a negative electrode, the method comprising steps of:
forming a cell by sequentially stacking a preliminary negative electrode, a separator, and a lithium metal;
immersing the cell in an electrolyte solution comprising a lithium salt and a solvent;
applying a current after the cell is immersed in the electrolyte solution comprising the lithium salt and the solvent;
separating the preliminary negative electrode from the cell after removing the cell immersed in the electrolyte solution from the electrolyte solution;
washing the separated preliminary negative electrode;
performing a first drying on the washed preliminary negative electrode at room temperature; and
performing a second drying on the first dried preliminary negative electrode at a temperature ranging from 30° C. to 70° C. in a vacuum state.

2. The method of claim 1 , wherein the first drying is performed for 5 minutes to 2 hours.

3. The method of claim 1 , wherein the first drying is performed in a dry room.

4. The method of claim 1 , wherein the second drying is performed for 1 hour to 48 hours.

5. The method of claim 1 , wherein the preliminary negative electrode comprises a current collector and a preliminary negative electrode active material layer on the current collector, and
a loading amount of the preliminary negative electrode active material layer is in a range of 1 mg/cm 2 to 20 mg/cm 2 .

6. The method of claim 1 , wherein an intensity of the current is in a range of 0.1 mA/cm 2 to 10 mA/cm 2 .

7. The method of claim 1 , wherein the preliminary negative electrode is charged from a state of charge of 5% to a state of charge of 50% by the current applied.

8. The method of claim 1 , wherein the step of applying the current is performed while applying pressure to the cell.

9. The method of claim 8 , wherein the pressure is in a range of 10 kPa to 3,500 kPa.

10. A method of preparing a negative electrode, the method comprising steps of:
forming a pre-lithiation structure by bonding a preliminary negative electrode and a lithium metal;
immersing the pre-lithiation structure in an electrolyte solution comprising a lithium salt and a solvent;
aging the pre-lithiation structure after the pre-lithiation structure is immersed in the electrolyte solution comprising the lithium salt and the solvent;
separating the preliminary negative electrode from the pre-lithiation structure after removing the pre-lithiation structure immersed in the electrolyte solution from the electrolyte solution;
washing the separated preliminary negative electrode;
performing a first drying on the washed preliminary negative electrode at room temperature; and
performing a second drying on the first dried preliminary negative electrode at a temperature ranging from 30° C. to 70° C. in a vacuum state.

11. The method of claim 10 , wherein the aging is performed for 0.01 hours to 10 hours.

12. The method of claim 10 , wherein the first drying is performed for 5 minutes to 2 hours.

13. The method of claim 10 , wherein the first drying is performed in a dry room.

14. The method of claim 10 , wherein the second drying is performed for 1 hour to 48 hours.

15. The method of claim 10 , wherein the preliminary negative electrode comprises a current collector and a preliminary negative electrode active material layer on the current collector, and
a loading amount of the preliminary negative electrode active material layer is in a range of 1 mg/cm 2 to 20 mg/cm 2 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Chae Oh Byong
• Kim Ye Ri
• Lee Su Yeon
• Hwang Seung Hae

Classifications

• H01M8/04014

  Heat exchange using gaseous fluids; Heat exchange by combustion of reactants · CPC title

• H01M8/04074

  Heat exchange unit structures specially adapted for fuel cell · CPC title

• H01M8/04089

  of gaseous reactants · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/0569

  characterised by the solvents · CPC title