Crosslinked polymer binders for electrochemical energy storage devices

Patent metadata

Field	Value
Publication number	US-11069894-B2
Application number	US-201615780861-A
Country	US
Kind code	B2
Filing date	Dec 5, 2016
Priority date	Dec 4, 2015
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

An electrochemical storage device including a conductive material and an electrochemical storage device material held together by a covalently crosslinked binder matrix. A method of forming an electrode for an electrochemical storage device, the method including the steps of: mixing electrochemical storage device material, conductive material, linear polymer, and crosslinker with one or more solvents, the resultant mixture forming an electrode slurry, crosslinking the linear polymer with the crosslinker to thereby create a covalently crosslinked polymer network of the polymer and crosslinker, the crosslinked polymer network physically or chemically binding together the electrochemical storage device material and the conductive material.

First claim

What is claimed is:

1. An electrode for an electrochemical storage device comprising:
a conductive material and an electrochemical energy storage material held together by a covalently crosslinked polymer binder matrix wherein the covalently crosslinked polymer binder matrix is a crosslinked network formed of linear polymer crosslinked with a crosslinker having a glass transition temperature of less than 50° C. and wherein the linear polymer is selected from carboxymethylcellulose (CMC) and Polyacrylic acid (PAA).

2. The electrode of claim 1 , wherein said conductive material is carbon black, graphene, carbon nanotube, or other carbonaceous materials.

3. The electrode of claim 1 , wherein said electrochemical energy storage material is selected from silicon, carbon, tin, antimony, cobalt, iron, lithium nickel manganese cobalt oxide, lithium nickel manganese oxide, lithium manganese oxide, lithium iron phosphate, lithium cobalt oxide, lithium nickel-cobalt-aluminum oxides, sulfur, lithium sulfide, iron fluoride, cupper fluoride, and any combination of above materials.

4. The electrode of claim 1 , wherein the linear polymer includes a polymer backbone and crosslinking reactive groups as side chains off of the polymer backbone.

5. The electrode of claim 4 , where said crosslinking reactive groups are provided by carboxylic acid groups, amine groups, hydroxyl groups, phosphoric acid groups, amine groups, and thiol groups.

6. The electrode of claim 4 , wherein said crosslinker is telechelic, said crosslinking reactive groups being end groups of the crosslinker.

7. The electrode of claim 4 wherein said crosslinker includes crosslinking reactive groups selected from hydroxyl groups, amine groups, phosphoric acid groups or thiol groups.

8. The electrode of claim 1 wherein said crosslinker is

with R=NH2, or OH.

9. The electrode of claim 1 , wherein the ratio of the weight of the polymer to the weight of crosslinker is between 100:1 to 5:1.

10. The electrode of claim 1 , wherein crosslinker has a glass transition temperature of less than 25° C.

11. A method of forming an electrode of claim 1 for an electrochemical storage device, the method comprising the steps of:
mixing electrochemical energy storage material, conductive material, linear polymer, and crosslinker with one or more solvents, the resultant mixture forming an electrode slurry, crosslinking the polymer with the crosslinker to thereby create a covalently crosslinked polymer network formed of the linear polymer crosslinked with the crosslinker, the crosslinked polymer network physically or chemically binding together the electrochemical energy storage material and the conductive material, crosslinker having a glass transition temperature of less than 50° C. and wherein the linear polymer is selected from carboxymethylcellulose (CMC) and Polyacrylic acid (PAA).

12. The method as in claim 11 , wherein said step of mixing includes the steps of:
mixing the electrochemical energy storage material, the conductive material, and the polymer in a polymer solvent that dissolves the polymer, the polymer solvent being present in a suitable amount to provide a uniform slurry;
mixing the crosslinker with a solvent to create a crosslinker stock solution; and
mixing together the uniform slurry and the crosslinker stock solution.

Assignees

• Zhu Yu
• Zou Feng
• Univ Akron

Inventors

• Zhu Yu
• Zou Feng

Classifications

• H01B1/24

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

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/622 Primary

  being polymers · CPC title

• H01M4/139

  Processes of manufacture · CPC title

• H01M4/625

  Carbon or graphite · CPC title