Method for manufacturing slurry for positive electrode of nonaqueous electrolyte secondary battery and slurry for positive electrode of nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11251418-B2
Application number	US-201815900559-A
Country	US
Kind code	B2
Filing date	Feb 20, 2018
Priority date	Feb 8, 2016
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

Provided is a method for manufacturing a slurry for a positive electrode of a nonaqueous electrolyte secondary battery containing an alkali metal complex oxide, the method making it possible to reliably deaerate surplus carbonic acid gas after an alkali component of a slurry containing the alkali metal complex oxide is neutralized within a short period of time. The method for manufacturing a slurry for a positive electrode of a nonaqueous electrolyte secondary battery includes a step of manufacturing an electrode slurry including a step of performing a neutralization treatment on an alkali component in the slurry by using inorganic carbon dissolved in a solvent of the slurry and a step of deaerating the inorganic carbon in the slurry as carbonic acid gas by causing cavitation.

First claim

What is claimed is:

1. A method for manufacturing a slurry, the method comprising:
performing, by a dispersing and mixing apparatus, a dispersing and mixing step of dispersing and mixing a powder and a solvent to generate a preliminary slurry that comprises a positive electrode active material;
performing, by the dispersing and mixing apparatus after the dispersing and mixing apparatus performs the dispersing and mixing step, a neutralizing step of producing a primary neutralized slurry by neutralizing the preliminary slurry; and
performing, by the dispersing and mixing apparatus after the dispersing and mixing apparatus performs the neutralizing step, a deaerating step of producing a secondary neutralized slurry by deaerating the primary neutralized slurry,
wherein the deaerating step comprises applying, to the primary neutralized slurry, a shearing force in a manner that causes cavitation.

2. The method according to claim 1 , wherein water is used as the solvent.

3. The method according to claim 1 , wherein the neutralizing step comprises adding carbonic acid gas to the preliminary slurry.

4. The method according to claim 3 , wherein the carbonic acid gas in the solvent is used to generate an inorganic carbon in the solvent.

5. The method according to claim 3 , wherein a pressure of the carbonic acid gas is equal to or higher than 0.12 MPa and equal to or lower than 100 MPa.

6. The method according to claim 3 , wherein a pressure of the carbonic acid gas is equal to or higher than 0.2 MPa and equal to or lower than 50 MPa.

7. The method according to claim 3 , wherein a pressure of the carbonic acid gas is equal to or higher than 0.3 MPa and equal to or lower than 10 MPa.

8. The method according to claim 3 , wherein the deaerating step comprises causing, by the dispersing and mixing apparatus, cavitation to deaerate an inorganic carbon in the primary neutralized slurry.

9. The method according to claim 1 , wherein the secondary neutralized slurry is for a positive electrode of a nonaqueous electrolyte secondary battery.

10. The method according to claim 9 , wherein the nonaqueous electrolyte secondary battery comprises an alkali metal complex oxide.

11. The method according to claim 10 , wherein the alkali metal complex oxide is a lithium complex oxide.

12. The method according to claim 1 , wherein the preliminary slurry further comprises a binder and a conductive material.

13. The method according to claim 12 , wherein with respect to a total amount of the positive electrode active material, the binder, and the conductive material:
an amount of the positive electrode active material is 60% to 99% by mass,
an amount of the binder is 0.1% to 25% by mass, and
an amount of the conductive material is 0.1% to 10% by mass.

14. The method according to claim 12 , wherein with respect to a total amount of the positive electrode active material, the binder, and the conductive material:
an amount of the positive electrode active material is 80% to 95% by mass,
an amount of the binder is 0.5% to 15% by mass, and
an amount of the conductive material is 0.5% to 5% by mass.

15. The method according to claim 1 , wherein the secondary neutralized slurry is recirculated to the dispersing and mixing apparatus to be used in the neutralizing step.

Assignees

• Nihon Spindle Mfg Co Ltd
• Aist

Inventors

• Sakamoto Taichi
• Mukai Takashi
• IKEUCHI Yuta
• Yamashita Naoto
• Yanagida Masahiro
• Asami Keiichi
• Onishi Keiichiro

Classifications

• C01G53/42

  containing alkali metals, e.g. LiNiO2 · CPC title

• C01G45/1242

  of the type (Mn2O4)-, e.g. LiMn2O4 or Li(MxMn2-x)O4 · CPC title

• H01M4/1391 Primary

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• C01G51/42

  containing alkali metals, e.g. LiCoO2 · CPC title