HIGH SOLIDS CONTENT PASTE FORMULATIONS FOR SECONDARY BATTERY ELECTRODE

• US 20170288232A1
• Filed: 09/25/2015
• Published: 10/05/2017
• Est. Priority Date: 09/26/2014
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: HERLE, Subramanya P.
• Granted Patent: US 10,707,489 B2
• Time in Patent Office: Days
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H01M 4/0414 by screen printing
• CPC Class Codes: H01M 4/139 Processes of manufacture
• CPC Class Codes: H01M 4/583 Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/622 being polymers
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A high solids content paste for fabrication of secondary battery electrodes may comprise: a negative active material or a positive active material; a binder; a solvent; and a hyperdispersant; wherein the high solids content paste has a specific viscosity chosen for a particular coating tool and a composition such that the high solids content paste will maintain a deposited shape after coating at least until the high solids content paste has dried and wherein the dry coating thickness is in the range of 5 microns to 300 microns. The high solids content paste with negative active material has a viscosity in the range of 30,000 cP to 45,000 cP and a corresponding density of 1.40 g/cc to 1.43 g/cc. The high solids content paste with positive active material has a viscosity in the range of 25,479 cP to 47,184 cP and a corresponding density of 2.72 g/cc to 2.73 g/cc.

Claims

1. A high solids content paste for fabrication of secondary battery electrodes, comprising:

an active material chosen from the group consisting of a negative active material and a positive active material;

a binder;

a solvent; and

a hyperdispersant;

wherein said high solids content paste has a specific viscosity chosen for a particular coating tool and a composition such that said high solids content paste will maintain a deposited shape after coating at least until said high solids content paste has dried and wherein the dry coating thickness is in the range of 5 microns to 300 microns.

2. The high solids content paste of claim 1, wherein said active material is a negative active material comprising graphite particles.

3. The high solids content paste of claim 2, wherein said binder comprises at least one of carboxyl-methyl-cellulose, hydroxy-ethyl-cellulose, poly-methyl-methacrylate and poly-ethyl-methacrylate.

4. The high solids content paste of claim 2, wherein said solvent comprises water.

5. The high solids content paste of claim 4, wherein said high solids content paste has a viscosity in the range of 30,000 cP to 45,000 cP and a corresponding density of 1.40 g/cc to 1.43 g/cc.

6. The high solids content paste of claim 1, wherein said active material is positive active material.

7. The high solids content paste of claim 6, wherein said high solids content paste is formulated for use to form a sintered sheet comprising positive active material for use as a substrate for electrochemical energy storage device fabrication.

8. The high solids content paste of claim 7, wherein said sintered sheet of positive active material has a thickness in the range of 3 microns to 260 microns.

9. The high solids content paste of claim 7, wherein said sintered sheet of positive active material has a thickness in the range of 10 microns to 60 microns.

10. The high solids content paste of claim 6, wherein said solvent comprises an organic solvent.

11. The high solids content paste of claim 6, wherein said high solids content paste has a viscosity in the range of 25,479 cP to 47,184 cP and a corresponding density of 2.72 g/cc to 2.73 g/cc.

12. The high solids content paste of claim 6, further comprising carbon solids.

13. A method of preparing a high solids content paste for fabrication of secondary battery electrodes, comprising:

providing an active material chosen from the group consisting of a negative active material and a positive active material;

wetting said active material to form wetted active material;

providing a binder and a solvent;

combining said binder with said solvent to form a viscous binder mixture;

combining in a low shear mixer said wetted active material and said viscous binder mixture to form a paste;

providing a hyperdispersant; and

adding said hyperdispersant to said paste, to form said high solids content paste with a specific viscosity.

14. A method of preparing a high solids content paste for fabrication of secondary battery electrodes, comprising:

providing an active material chosen from the group consisting of a negative active material and a positive active material;

solid phase mixing of said active material to form a solids mixture;

providing a binder and a solvent;

combining said solids mixture with said binder and said solvent to form a paste;

providing a hyperdispersant; and

adding said hyperdispersant to said paste, to form said high solids content paste with a specific viscosity.

15. The method of claim 14, further comprising providing carbon solids and solid phase mixing said carbon solids with said active material to form said solids mixture.