Lower pyrolysis temperature binder for silicon-dominant anodes

Patent metadata

Field	Value
Publication number	US-11450841-B2
Application number	US-201916681401-A
Country	US
Kind code	B2
Filing date	Nov 12, 2019
Priority date	Nov 12, 2019
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

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

The invention 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 94% and up to 97% by weight of the anode; and
a pyrolytic carbon structure comprising a framework around the plurality of silicon particles of the active material layer,
wherein the pyrolytic carbon structure comprises between 4% and 5% of the weight of the anode after pyrolysis below 600° C.

2. The anode according to claim 1 , wherein a battery comprises the anode.

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

4. The anode according to claim 3 , wherein an onset of pyrolysis occurs below 500° C.

5. The anode according to claim 4 , wherein pyrolysis produces carbonization of the PAI below 600° C.

6. The anode according to claim 3 , wherein:
the active material layer comprises a carbon-based additive; and
the carbon-based additive comprises between 2% and 6% of weight of the anode after pyrolysis below 600° C.

7. The anode according to claim 1 , wherein:
the active material layer comprises an additive; and
the additive comprises at least one of ECP, ECP600, Super-P, and SLP.

8. 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 pyrolytic carbon framework; and
wherein the pyrolytic carbon structure comprises between 4% and 5% of the weight of the anode after pyrolysis below 600° C.

9. The battery according to claim 8 , wherein the pyrolytic carbon framework comprises glassy carbon from pyrolytic decomposition of polyamide-imide (PAI).

10. The battery according to claim 9 , wherein an onset of decomposition occurs below 500° C.

11. The battery according to claim 9 , wherein carbonization of the PAI occurs below 600° C.

12. The battery according to claim 8 , wherein:
the active material layer comprises a carbon-based additive; and
the carbon-based additive comprises between 2% and 6% of weight of the anode.

13. The battery according to claim 8 , wherein:
the active material layer comprises an additive; and
the additive comprises at least one of ECP, ECP600, Super-P, and SLP.

Assignees

• Enevate Corp

Inventors

• Chhorng Monika
• Lee David J
• Kamath Rahul

Classifications

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/621

  Binders · CPC title

• H01M4/622 Primary

  being polymers · CPC title