Nano-fibers for electrical power generation

• US 9,172,099 B2
• Filed: 10/31/2011
• Issued: 10/27/2015
• Est. Priority Date: 11/15/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Zou, Lijun, Fuller, Timothy J., Schoeneweiss, Michael R.
• Primary Examiner(s): Kelly, Cynthia H
• Assistant Examiner(s): WILLS, MONIQUE M
• Application Number:
  US13/285,296
• Publication Number:
  US 20120122011A1
• Time in Patent Office: 1,457 Days
• Field of Search: 429/479, 429/249
• US Class Current: 1/1
• CPC Class Codes: C08J 2371/12 Polyphenylene oxides
• CPC Class Codes: C08J 5/2206 based on organic and/or inorganic macromolecular compounds
• CPC Class Codes: C08J 5/2262 containing fluorine
• CPC Class Codes: D01D 5/0084 Coating by electro-spinning, i.e. the electro-spun fibres are not removed from the collecting device but remain integral with it, e.g. coating of prostheses
• CPC Class Codes: D01F 6/74 from polycondensates of cyclic compounds, e.g. polyimides, polybenzimidazoles
• CPC Class Codes: D01F 6/78 from copolycondensation products
• CPC Class Codes: H01M 50/426 Fluorocarbon polymers
• CPC Class Codes: H01M 8/0239 Organic resins; Organic polymers
• CPC Class Codes: H01M 8/0289 Means for holding the electrolyte solid polymer electrolytes H01M8/1018
• CPC Class Codes: H01M 8/1018 Polymeric electrolyte materials
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fibrous sheet for fuel cell or battery applications is formed by electrospinning a fluorinated ion-conducting polymer solution to form an agglomeration of fibers.

Claims

1. A method of making a device with a fibrous sheet, the method comprising:

providing a solution comprising a fluorinated polymer;

forming an aggregation of fibers, the aggregation of fibers formed by electrospinning the solution of a fluorinated ion conducting polymer;

forming the fibrous sheet from the aggregation of fibers;

mechanically compacting the fibrous sheet to increase fiber density;

welding fibers together at fiber intersection points by exposing the fibers to a solvent vapor; and

interposing the fibrous sheet between an anode and a cathode.

2. The method of claim 1 wherein the anode and cathode are battery components and the fibrous sheet is a battery separator.

3. The method of claim 1 further comprising placing the fibrous sheet between a catalyst layer and a bipolar metal plate wherein the fibrous sheet is a gas diffusion layer.

4. The method of claim 1 wherein the fluorinated polymer comprises a polymer having perfluorocyclobutyl moieties.

5. The method of claim 4 wherein the fluorinated polymer includes pendant side chains.

6. The method of claim 4 wherein the perfluorocyclobutyl moieties are:

7. The method of claim 4 wherein the fluorinated polymer comprises polymer segments 1 and 2:

[E₁(SO₂X)_d]-P₁-Q₁-P₂ 

 

1

E₂-P₃-Q₂-P₄ 

 

2

wherein;

E₁(SO₂X)_d is a sulfonated aromatic-containing moiety;

E₁ is an aromatic-containing moiety;

E₂ is an unsulfonated aromatic-containing and/or aliphatic-containing moiety;

X is an —

OH, a halogen, an ester, or

8. The method of claim 4 wherein the fluorinated polymer comprises polymer segments 3 and 4:

9. The method of claim 4 wherein the fluorinated polymer comprises polymer segments 5 and 6:

E₁(SO₂X)_d-P₁-Q₁-P₂ 

 

5

E₂-P₃-Q₂-P₄ 

 

6

connected by a linking group L₁ to form polymer units 7 and 8;

10. The method of claim 4 wherein the fluorinated polymer comprises polymer segments 9 and 10:

E₁(SO₂X)_d-P₁-Q₁-P₂ 

 

9

E₂(SO₂X)_f-P₃ 

 

10

wherein;

E₁, E₂ is an aromatic or aliphatic-containing moiety wherein at least one of E₁ and E₂ include an aromatic group substituted with —

SO₂X;

X is an —

OH, a halogen, an ester, or

11. The method of claim 1 wherein the fluorinated polymer comprises a perfluorosulfonic acid polymer.

12. The method of claim 1 wherein the fluorinated polymer comprises a copolymer containing a polymerization unit based on a perfluorovinyl compound represented by:

CF₂═

CF—

(OCF₂CFX¹)_m—

O_r—

(CF₂)_q—

SO₃H

where m represents an integer of from 0 to 3, q represents an integer of from 1 to 12, r represents 0 or 1, and X¹ represents a fluorine atom or a trifluoromethyl group and a polymerization unit based on tetrafluoroethylene.

13. The method of claim 1 wherein the solution further comprises a fluoro-elastomer or a fluoro-rubber.

14. The method of claim 1 wherein fibers have an average width from about 5 nanometers to about 10 microns.

15. The method of claim 1 wherein the fibers have an average width from about 10 nanometers to about 5 microns.

16. The method of claim 1 wherein the fluorinated polymer comprises a sulfonated or unsulfonated ion-conducting polymer having perfluorocyclobutyl moieties.

20. The method of claim 1 wherein the fluorinated polymer has the following formula:

17. A fibrous sheet made by a method comprising:

providing a solution comprising a fluorinated polymer;

forming an aggregation of fibers, the aggregation of fibers formed by electrospinning the solution of a fluorinated ion conducting polymer;

forming the fibrous sheet from the aggregation of fibers;

mechanically compacting the fibrous sheet to increase fiber density;

welding fibers together at fiber intersection points by exposing the fibers to a solvent vapor; and

interposing the fibrous sheet between an anode and a cathode.

18. The fibrous sheet of claim 17 wherein the fluorinated polymer comprises a component selected from the group consisting of a polymer having perfluorocyclobutyl moieties, a perfluorosulfonic acid polymer, and combinations thereof.

19. The fibrous sheet of claim 17 wherein the solution further comprises a fluoro-elastomer or a fluoro-rubber.