Methods of coating an electrically conductive substrate and related electrodepositable compositions

Patent metadata

Field	Value
Publication number	US-9870844-B2
Application number	US-201514831047-A
Country	US
Kind code	B2
Filing date	Aug 20, 2015
Priority date	Nov 27, 2012
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A method of producing an electrode for a lithium ion battery is disclosed in which an electrically conductive substrate is immersed into an electrodepositable composition, the substrate serving as the electrode in an electrical circuit comprising the electrode and a counter-electrode immersed in the composition, a coating being applied onto or over at least a portion of the substrate as electric current is passed between the electrodes. The electrodepositable composition comprises: (a) an aqueous medium; (b) an ionic (meth)acrylic polymer; and (c) solid particles comprising: (i) lithium-containing particles, and (ii) electrically conductive particles, wherein the composition has a weight ratio of solid particles to ionic (meth)acrylic polymer of at least 4:1.

First claim

What is claimed is:

1. A method of producing an electrode for a lithium ion battery comprising:
immersing an electrically conductive substrate into an electrodepositable composition, the substrate serving as the electrode in an electrical circuit comprising the electrode and a counter-electrode immersed in the composition, a coating being applied onto or over at least a portion of the substrate as electric current is passed between the electrodes,
the electrodepositable composition comprising:
(a) an aqueous medium;
(b) an ionic (meth)acrylic polymer; and
(c) solid particles comprising:
(i) lithium-containing particles, and
(ii) electrically conductive particles; wherein the composition has a weight ratio of the solid particles to the ionic (meth)acrylic polymer of at least 4:1.

2. The method of claim 1 , wherein the substrate is a foil comprising aluminum, iron, copper, manganese, nickel, a combination thereof, and/or an alloy thereof.

3. method of claim 1 , wherein the ionic (meth)acrylic polymer is anionic.

4. The method of claim 1 , wherein the ionic (meth)acrylic polymer is prepared by organic solution polymerization techniques.

5. The method of claim 1 , wherein the ionic (meth)acrylic polymer is prepared by emulsion polymerization techniques.

6. The method of claim 1 , wherein the (meth)acrylic polymer is prepared by polymerizing a mixture of (meth)acrylic monomers including a (meth)acrylic acid monomer and at least partially neutralizing the (meth)acrylic polymer with a base.

7. The method of claim 6 in which the (meth)acrylic acid is present in the mixture in an amount of at least 30 percent by weight based on total weight of the mixture of (meth)acrylic monomers.

8. The method of claim 6 in which the mixture of (meth)acrylic monomers includes a monomer having a Tg of −20° C. or less.

9. The method of claim 8 , wherein the low Tg monomer is present in the mixture in amounts of at least 30 percent by weight based on total weight of (meth)acrylic monomer.

10. The method of claim 8 in which the low Tg monomer comprises 2-ethylhexyl acrylate and/or butyl acrylate.

11. The method of claim 1 , wherein the lithium-containing particles comprise LiCoO 2 , LiNiO 2 , LiFePO 4 , LiCoPO 4 , LiMnO 2 , LiMn 2 O 4 , Li(NiMnCo)O 2 , and/or Li(NiCoAl)O 2 .

12. The method of claim 1 , wherein the lithium-containing particles are present in an amount of at least 50 percent by weight, based on the total weight of the solids in the composition.

13. The method of claim 1 , wherein the electrically conductive particles comprise electrically conductive carbon particles.

14. The method of claim 13 , wherein electrically conductive carbon particles comprise carbon black.

15. The method of claim 1 , wherein the composition has a weight ratio of the lithium-containing particles to the electrically conductive particles in the composition of at least 3:1.

16. The method of claim 1 , wherein the composition has the weight ratio of the solid particles to the ionic (meth)acrylic polymer of at least 8:1.

17. The method of claim 1 , wherein the composition has a total solids content of 1 to 5 percent by weight, based on the total weight of the composition.

18. An electrodepositable composition comprising
(a) an aqueous medium;
(b) an ionic (meth)acrylic polymer; and
(c) solid particles comprising:
(i) lithium-containing particles, and
(ii) electrically conductive particles; wherein the composition has a weight ratio of the solid particles to the ionic (meth)acrylic polymer of at least 4:1.

19. The composition of claim 18 , wherein the weight ratio is at least 8:1.

20. The composition of claim 18 , wherein the ionic (meth)acrylic polymer is anionic.

21. The composition of claim 18 , wherein the ionic (meth)acrylic polymer is prepared by organic solution polymerization techniques.

22. The composition of claim 18 , wherein the ionic (meth)acrylic polymer is prepared by emulsion polymerization techniques.

23. The composition of claim 18 , wherein the (meth)acrylic polymer is prepared by polymerizing a mixture of (meth)acrylic monomers including a (meth)acrylic acid monomer and at least partially neutralizing the (meth)acrylic polymer with a base.

24. The composition of claim 23 in which the (meth)acrylic acid is present in the mixture in an amount of at least 30 percent by weight based on total weight of the mixture of (meth)acrylic monomers.

25. The composition of claim 23 in which the mixture of (meth)acrylic monomers includes a monomer having a Tg of −20° C. or less.

26. The composition of claim 25 , wherein the low Tg monomer is present in the mixture in amounts of at least 30 percent by weight based on total weight of (meth)acrylic monomer.

27. The composition of claim 25 in which the low Tg monomer comprises 2-ethylhexyl acrylate and/or butyl acrylate.

28. The composition of claim 18 , wherein the lithium-containing particles comprise LiCoO 2 , LiNiO 2 , LiFePO 4 , LiCoPO 4 , LiMnO 2 , LiMn 2 O 4 , Li(NiMnCo)O 2 , and/or Li(NiCoAl)O 2 .

29. The composition of claim 18 , wherein the lithium-containing particles are present in an amount of at least 50 percent by weight, based on the total weight of the solid particles.

30. The composition of claim 18 , wherein the electrically conductive particles comprise electrically conductive carbon particles.

31. The composition of claim 18 , wherein the composition has a weight ratio of the lithium-containing particles to the electrically conductive particles in the composition of at least 3:1.

32. The composition of claim 18 , wherein the composition has a total solids content of 1 to 5 percent by weight, based on the total weight of the composition.

Assignees

• Ppg Ind Ohio Inc

Inventors

• Daughenbaugh Randy E
• Hellring Stuart D

Classifications

• C25D13/02

  with inorganic material · CPC title

• C25D13/16

  Wires; Strips; Foils · CPC title

• H01M4/136

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title

• H01B1/24 Primary

  the conductive material comprising carbon-silicon compounds, carbon or silicon · CPC title

• C09D5/448

  characterised by the additives used (C09D5/4403 - C09D5/4476, C09D5/4492 take precedence) · CPC title