Gradient interface magnetic composites and methods therefor

• US 6,303,242 B1
• Filed: 12/10/1999
• Issued: 10/16/2001
• Est. Priority Date: 08/25/1994
• Status: Expired due to Fees

• Current Assignee: University of Iowa Research Foundation
• Original Assignee: University of Iowa Research Foundation
• Inventors: Leddy, Johna, Amarasinghe, Sudath, Zook, Lois Anne
• Primary Examiner(s): Reifsnyder, David A.
• Application Number:
  US09/458,058
• Time in Patent Office: 676 Days
• Field of Search: 429/10, 429/12, 429/127, 429/40, 210/222, 428/692
• US Class Current: 429/10
• CPC Class Codes: B03C 1/01 by addition of magnetic adjuvants
• CPC Class Codes: B03C 1/025 High gradient magnetic separators
• CPC Class Codes: B03C 1/034 characterised by the matrix elements
• CPC Class Codes: B03C 1/035 Open gradient magnetic separators, i.e. separators in which the gap is unobstructed, characterised by the configuration of the gap
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C23C 24/08 by application of heat or pressure and heat C23C24/04 takes precedence
• CPC Class Codes: C23C 30/00 Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process C23C26/00, C23C28/00 take precedence
• CPC Class Codes: C23C 6/00 Coating by casting molten material on the substrate
• CPC Class Codes: C25B 11/00 Electrodes; Manufacture thereof not otherwise provided for
• CPC Class Codes: C25D 3/54 of metals not provided for in groups C25D3/04 - C25D3/50
• CPC Class Codes: G21F 9/12 by absorption; by adsorption; by ion-exchange
• CPC Class Codes: H01F 1/0027 Thick magnetic films forming thick magnetic films H01F41/16
• CPC Class Codes: H01F 1/0054 Coated nanoparticles, e.g. nanoparticles coated with organic surfactant
• CPC Class Codes: H01F 1/009 bidimensional, e.g. nanoscale period nanomagnet arrays H01F10/007 takes precedence
• CPC Class Codes: H01F 10/007 ultrathin or granular films H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301
• CPC Class Codes: H01F 41/24 from liquids
• CPC Class Codes: H01F 41/26 using electric currents , e.g. electroplating
• CPC Class Codes: H01F 41/301 for applying ultrathin or granular layers ultrathin or granular layers H01F10/007
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 2300/0082 : Organic polymers
• CPC Class Codes: H01M 4/02 : Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/86 : Inert electrodes with catalytic activity, e.g. for fuel cells
• CPC Class Codes: H01M 4/8605 : Porous electrodes
• CPC Class Codes: H01M 4/8857 : Casting, e.g. tape casting, vacuum slip casting
• CPC Class Codes: H01M 4/8882 : Heat treatment, e.g. drying, baking
• CPC Class Codes: H01M 4/9083 : on carbon or graphite
• CPC Class Codes: H01M 4/926 : on carbon or graphite
• CPC Class Codes: H01M 8/1004 : characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1009 : with one of the reactants being liquid, solid or liquid-charged H01M8/12 takes precedence
• CPC Class Codes: H01M 8/249 : comprising two or more groupings of fuel cells, e.g. modular assemblies
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y10T 428/32 : Composite [nonstructural laminate] of inorganic material having metal-compound-containing layer and having defined magnetic layer

Abstract

Magnetic composites exhibit distinct flux properties due to gradient interfaces. The composites can be used to improve fuel cells and batteries and effect transport and separation of different species of materials, for example, transition metal species such as lanthanides and actinides. A variety of devices can be made utilizing the composites including a separator, an electrode for channeling flux of magnetic species, an electrode for effecting electrolysis of magnetic species, a system for channeling electrolyte species, a system for separating particles with different magnetic susceptibilities, improved fuel cells, batteries, and oxygen concentrators. Some composites can be used to make a separator for distinguishing between two species of materials and a flux switch to regulate the flow of a chemical species. Some composites can control chemical species transport and distribution. Other composites enable ambient pressure fuel cells having enhanced performance and reduced weight to be produced. Still other composites enable rechargeable batteries to be made that have longer secondary cycle life and improved output power. Methods involving these composites provide distinct ways for these composites to be utilized.

Claims

1. A fuel cell, comprising:

a first electrode having a surface and a magnetic composite cast on said surface; and

a second electrode, wherein a flux of oxygen is established between said first electrode and said second electrode, and wherein said first electrode enhances the kinetic efficiency of the reduction of oxygen to water.

2. The fuel cell as claimed in claim 1, wherein said fuel cell has a thermal signature below 100°

C.

3. The fuel cell of claim 1, wherein the first electrode is a cathode.

4. The fuel cell of claim 1, wherein a plurality of magnetic particles is attached to a surface of the first electrode, and wherein a conductive layer is attached to each of the magnetic particles.

5. A fuel cell, comprising:

a first electrode having a surface and a magnetic composite cast on said surface; and

a second electrode, wherein a flux of oxygen is established between said first electrode and said second electrode, and wherein said fuel cell has a thermal signature below 100°

C.

6. The fuel cell as claimed in claim 5, wherein said fuel cell has an outside covering comprised of a gas porous or permeable hydrocarbon material.

7. The fuel cell as claimed in claim 5, wherein the said fuel cell is approximately ⅜

inch thick.

8. The fuel cell as claimed in claim 5, wherein said fuel cell is flexible.

9. The fuel cell as claimed in claim 5, wherein said fuel cell is approximately the size of a letter sized piece of paper, capable of producing enough power to run electronic devices.

10. The fuel cell as claimed in claim 5, wherein said fuel cell can be confined to at least one confined geometry and volume, and may be flattened for use and used in at least one of said at least one confined geometry and volume.

11. The fuel cell as claimed in claim 5, wherein said fuel cell can produce up to at least 30 Watts of power.

12. A fuel cell, comprising:

a first electrode having a surface and a magnetic composite cast on said surface; and

a second electrode, wherein a flux of oxygen is established between said first electrode and said second electrode, and wherein a potential shift is produced at said first electrode.

13. A fuel cell having two electrodes and a flux of magnetic species between said two electrodes, wherein one of said two electrodes comprises:

a conductor; and

a composite magnetic material in surface contact with said conductor, said composite magnetic material having a plurality of transport pathways through said composite magnetic material to enhance the passage of said magnetic species to said conductor, thereby enhancing the kinetic efficiency of the electrolysis of said magnetic species.

14. A fuel cell having two electrodes and a flux of magnetic species between said two electrodes, wherein one of said two electrodes comprises:

a conductor; and

a composite magnetic material in surface contact with said conductor, said composite magnetic material having a plurality of transport pathways through said composite magnetic material to enhance the passage of said magnetic species to said conductor, thereby producing a potential shift at said one of said two electrodes.

15. An ambient pressure fuel cell, comprising:

a first electrode, having a surface and a magnetic composite cast on said surface, disposed in said fuel cell;

a second electrode disposed in said fuel cell; and

a fuel source having an established transport direction for constituents thereof disposed between said first electrode and said second electrode.

16. The fuel cell as claimed in claim 15, wherein said fuel cell is light-weight, flexibly packaged, and a high performance power source.

17. A fuel cell, comprising:

a first electrode having a surface and a magnetic composite cast on said surface; and

a second electrode, wherein an increased current is driven by a higher flux of oxygen established between said first electrode and said second electrode and the resultant higher surface concentration of oxygen.