Electrode with conductive interlayer and method thereof

Patent metadata

Field	Value
Publication number	US-12046759-B2
Application number	US-202217898050-A
Country	US
Kind code	B2
Filing date	Aug 29, 2022
Priority date	Sep 6, 2018
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

In an embodiment, a Li-ion battery electrode comprises a conductive interlayer arranged between a current collector and an electrode active material layer. The conductive interlayer comprises first conductive additives and a first polymer binder, and the electrode active material layer comprises a plurality of active material particles mixed with a second polymer binder (which may be the same as or different from the first polymer binder) and second conductive additives (which may be the same as or different from the first conductive additives). In a further embodiment, the Li-ion battery electrode may be fabricated via application of successive slurry formulations onto the current collector, with the resultant product then being calendared (or densified).

First claim

The invention claimed is:

1. A Li-ion battery electrode, comprising:
a current collector;
an electrode layer arranged on the current collector, the electrode layer comprising active material particles mixed with a binder and conductive additives,
wherein:
the active material particles are composite particles comprising an active material and exhibiting an average particle size in a range from about 0.2 μm to about 10 μm and an average areal capacity loading in a range of about 3 mAh/cm 2 to about 12 mAh/cm 2 ;
the conductive additives comprise single-walled carbon nanotubes;
a concentration of the single-walled carbon nanotubes in a bulk of the electrode layer is in a range of 0.20 wt. % to 0.40 wt. %; and
a G/D band ratio of a Raman spectrum at a conductive interlayer of the electrode layer that is separate from the bulk of the electrode layer and is arranged between the bulk of the electrode layer and the current collector is in a range of about 20 to about 50.

2. The Li-ion battery electrode of claim 1 , wherein the active material particles comprise silicon (Si).

3. The Li-ion battery electrode of claim 2 , wherein the active material particles comprise nano-sized Si particles.

4. The Li-ion battery electrode of claim 2 , wherein the active material particles comprise carbon (C).

5. The Li-ion battery electrode of claim 1 , wherein the binder comprises a water-soluble polymer or water-dispersible polymer.

6. The Li-ion battery electrode of claim 1 , wherein the binder comprises one or more of carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), and polyvinyl alcohol (PVA).

7. The Li-ion battery electrode of claim 1 , wherein the conductive additives additionally comprise double-walled carbon nanotubes and/or multi-walled carbon nanotubes.

8. The Li-ion battery electrode of claim 1 , wherein an average thickness of the conductive interlayer ranges from around 25 nm to around 500 nm.

9. The Li-ion battery electrode of claim 1 , wherein the current collector is a metal foil with a thickness in a range from around 4 μm to around 15 μm.

10. The Li-ion battery electrode of claim 1 , wherein the current collector is an electrodeposited metal foil.

11. A Li-ion battery comprising the Li-ion battery electrode of claim 1 .

12. A method of making a Li-ion battery electrode, the method comprising:
mixing a binder, a solvent composition, conductive additives, and active material particles to form a uniform slurry;
coating a current collector with the slurry to obtain a slurry coating;
drying the slurry coating to obtain an electrode layer on the current collector; and
calendaring the electrode layer until a desired density is achieved,
wherein:
the active material particles are composite particles comprising an active material and exhibiting an average particle size in a range from about 0.2 μm to about 10 μm and an average areal capacity loading in a range of about 3 mAh/cm 2 to about 12 mAh/cm 2 ;
the conductive additives comprise single-walled carbon nanotubes;
a concentration of the single-walled carbon nanotubes in a bulk of the electrode layer is in a range of 0.20 wt. % to 0.40 wt. %; and
a G/D band ratio of a Raman spectrum at a conductive interlayer of the electrode layer that is separate from the bulk of the electrode layer and is arranged between the bulk of the electrode layer and the current collector is in a range of about 20 to about 50.

13. The method of claim 12 , wherein the solvent composition comprises water.

14. The method of claim 12 , wherein the solvent composition comprises N-methyl-2-pyrrolidone.

15. The method of claim 12 , wherein the active material particles comprise silicon (Si).

16. The method of claim 15 , wherein the active material particles comprise nano-sized Si particles.

17. The method of claim 15 , wherein the active material particles comprise carbon (C).

18. The method of claim 12 , wherein the binder comprises a water-soluble polymer or water-dispersible polymer.

19. The method of claim 12 , wherein the binder comprises one or more of carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), polyvinylidene fluoride (PVDF), polyacrylic acid (PAA), and polyvinyl alcohol (PVA).

20. The method of claim 12 , wherein the conductive additives additionally comprise double-walled carbon nanotubes and/or multi-walled carbon nanotubes.

21. The method of claim 12 , wherein an average thickness of the conductive interlayer ranges from around 25 nm to around 500 nm.

22. The method of claim 12 , wherein the current collector is a metal foil with a thickness in a range from around 4 μm to around 15 μm.

23. The method of claim 12 , wherein the current collector is an electrodeposited metal foil.

24. The Li-ion battery electrode of claim 1 , wherein the concentration of the single-walled carbon nanotubes in the bulk of the electrode layer is in a range of 0.27 wt. % to 0.40 wt. %.

Assignees

• Sila Nanotechnologies Inc

Inventors

• Yushin Gleb
• Yen Justin
• Steiger Jens
• Zsoldos Eniko
• Fevre Mareva
• Kajdos Adam
• Wang Weimin

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/623

  fluorinated polymers · CPC title

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/362

  Composites · CPC title