Lower pyrolysis temperature binder for silicon-dominant anodes

Patent metadata

Field	Value
Publication number	US-11901543-B2
Application number	US-202217945790-A
Country	US
Kind code	B2
Filing date	Sep 15, 2022
Priority date	Nov 12, 2019
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

Systems and methods are provided for carbon additives for direct coating of silicon-dominant anodes. An example composition for use in directly coated anodes may include a silicon-dominated anode active material, a carbon-based binder, and a carbon-based additive, with the composition being configured for low-temperature pyrolysis. The low-temperature pyrolysis may be conducted at <600° C. An anode may be formed using a direct coating process of the composition on a current collector. The anode active material yields silicon constituting between 86% and 97% of weight of the formed anode after pyrolysis. The carbon-based additive yields carbon constituting between 2% and 6% of weight of the formed anode after pyrolysis.

First claim

What is claimed is:

1. An anode, the anode comprising:
a current collector; and
an active material layer on the current collector, the active material layer comprising:
a plurality of silicon particles providing the anode with a silicon content of greater than 95% and up to 97% by weight of the anode; and
a pyrolytic carbon structure around the plurality of silicon particles of the active material layer, wherein the pyrolytic carbon structure comprises between 2% and 6% by weight of the anode.

2. The anode of claim 1 , wherein the pyrolytic carbon structure comprises between 4% and 5% by weight of the anode.

3. The anode of claim 1 , wherein the pyrolytic carbon structure comprises between 2% and 6% by weight of the anode after pyrolysis below 600° C.

4. The anode of claim 1 , wherein the pyrolytic carbon structure comprises between 4% and 5% by weight of the anode after pyrolysis below 600° C.

5. The anode of claim 1 , wherein the pyrolytic carbon structure comprises a glassy carbon.

6. The anode of claim 1 , wherein the pyrolytic carbon structure comprises a glassy carbon from pyrolysis of polyamide-imide (PAI).

7. The anode of claim 6 , wherein an onset of pyrolysis of the PAI occurs below 500° C.

8. The anode of claim 1 , comprising an adhesive layer between the active material layer and the current collector.

9. The anode of claim 1 , wherein:
the current collector comprises copper; and
an interface between the current collector and the active material layer lacks a formation of Cu×Si material.

10. The anode of claim 1 , wherein:
the current collector comprises nickel; and
an interface between the current collector and the active material layer lacks a formation of Ni×Si material.

11. An anode, the anode comprising:
a current collector; and
an active material layer on the current collector, the active material layer comprising:
a plurality of silicon particles providing the anode with a silicon content of at least 86% by weight of the anode; and
a carbon structure around the plurality of silicon particles of the active material layer, wherein the carbon structure comprises between 2% and 6% by weight of the anode.

12. The anode of claim 11 , wherein the carbon structure comprises between 4% and 5% by weight of the anode.

13. The anode of claim 11 , wherein the carbon structure comprises between 4% and 5% by weight of the anode after pyrolysis below 600° C.

14. The anode of claim 11 , wherein:
the active material layer comprises an additive; and
the additive comprises at least one of ECP, ECP600, Super-P, and SLP.

15. A battery, comprising:
an anode;
a cathode; and
a separator between the anode and the cathode, wherein the anode comprises a current collector and an active material layer on the current collector;
wherein the active material layer comprises a silicon content of greater than 94% and up to 97% by weight of the anode;
wherein the active material layer comprises a carbon structure; and
wherein the carbon structure comprises between 4% and 5% of weight of the anode.

16. The battery of claim 15 , wherein the carbon structure comprises glassy carbon from pyrolytic decomposition of polyamide-imide (PAI) below 600° C.

17. The battery of claim 15 , wherein the carbon structure comprises glassy carbon from pyrolytic decomposition of a binder below 600° C.

18. The battery of claim 15 , wherein:
the current collector comprises copper; and
an interface between the current collector and the active material layer lacks a formation of Cu×Si material.

19. The battery of claim 15 , wherein:
the current collector comprises nickel; and
an interface between the current collector and the active material layer lacks a formation of Ni×Si material.

Assignees

• Enevate Corp

Inventors

• Chhorng Monika
• Lee David J
• Kamath Rahul

Classifications

• H01M4/0471 Primary

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/1395

  of electrodes based on metals, Si or alloys · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title