Sulfur-carbon material

• US 8,173,302 B2
• Filed: 06/11/2008
• Issued: 05/08/2012
• Est. Priority Date: 06/11/2008
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation, University of Waikato
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation), University of Waikato
• Inventors: Stamm, Kimber L., Richard, Monique N., Nazar, Linda F., Ji, Xiulei, Lee, Kyu-Tae
• Primary Examiner(s): Le, Emily
• Assistant Examiner(s): Forrest, Michael
• Application Number:
  US12/136,846
• Publication Number:
  US 20090311604A1
• Time in Patent Office: 1,427 Days
• Field of Search: None
• US Class Current: 429/231.8
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/581 Chalcogenides or intercalation compounds thereof
• CPC Class Codes: H01M 4/583 Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 428/249967 Inorganic matrix in void-containing component
• CPC Class Codes: Y10T 428/249978 Voids specified as micro

Abstract

An electrode material having carbon and sulfur is provided. The carbon is in the form of a porous matrix having nanoporosity and the sulfur is sorbed into the nanoporosity of the carbon matrix. The carbon matrix can have a volume of nanoporosity between 10 and 99%. In addition, the sulfur can occupy between 5 to 99% of the nanoporosity. A portion of the carbon structure that is only partially filled with the sulfur remains vacant allowing electrolyte egress. In some instances, the nanoporosity has nanopores and nanochannels with an average diameter between 1 nanometer and 999 nanometers. The sulfur is sorbed into the nanoporosity using liquid transport or other mechanisms providing a material having intimate contact between the electronically conductive carbon structure and the electroactive sulfur.

Claims

1. A material comprising:

carbon and sulfur;

said carbon in the form of a porous matrix having nanoporosity in the form of nanopores and nanochannels having an average diameter between 1 nanometer and 50 nanometers; and

said sulfur sorbed into a portion of said nanoporosity of said carbon matrix and in the form of nanoparticles having an external dimension that is greater than a minimal diameter of said nanoporosity where said nanoparticles are located such that said nanoparticles are trapped within said carbon matrix;

said sulfur occupying more than 5% and less than 100% said nanoporosity such that there is free volume available within said nanoporosity.

2. The material of claim 1, wherein said matrix has between 10 and 99 percent by volume of said nanoporosity.

3. The material of claim 2, wherein said sulfur occupies more than 50% and less than 100% said nanoporosity.

4. The material of claim 2, wherein said sulfur occupies more than 75% and less than 100% said nanoporosity.

5. The material of claim 1, further comprising a coating, said coating selected from the group consisting of organic and inorganic components.

6. The material of claim 1, wherein at least part of said sulfur is an elemental sulfur particle.

7. The material of claim 1, wherein at least part of said sulfur compound is a sulfur compound particle.

8. The material of claim 1, wherein said nanopores and said nanochannels have an average diameter between 1 nanometer and 30 nanometers.

9. The material of claim 1, wherein said nanopores and said nanochannels have an average diameter between 1 nanometer and 20 nanometers.

10. An electrode comprising the material according to claim 1.

11. The electrode of claim 10, further comprising a binding compound, other additives and combinations thereof.

12. A battery having:

a negative electrode;

an electrolyte; and

a positive electrode according to claim 10.

13. A material comprising:

carbon and sulfur;

said carbon in the form of a porous matrix in the form of nanopores and nanochannels defining a porosity, said nanopores and said nanochannels having an average diameter between 1 nanometer and 50 nanometers; and

said sulfur sorbed into a portion of said nanopores and said nanochannels of said carbon matrix in the form of nanoparticles having an external dimension that is greater than a minimal diameter of said nanoporosity where said nanoparticles are located such that said nanoparticles are trapped within said porous matrix and occupy more than 5% and less than 100% of said porosity such that there is free volume available within said porosity.

14. The material of claim 13, wherein at least part of said sulfur is an elemental sulfur particle.

15. The material of claim 13, wherein said at least part of said sulfur is present as a sulfur compound particle.

16. A battery having a sulfur-carbon electrode, the battery comprising:

a negative electrode containing lithium;

an electrolyte;

a positive electrode, said positive electrode having;

a porous carbon matrix having nanopores and nanochannels defining a porosity, said nanopores and said nanochannels having an average diameter between 1 nanometer and 50 nanometers; and

sulfur sorbed into a portion of said nanopores and said nanochannels of said carbon matrix in the form of nanoparticles having an external dimension that is greater than a minimal diameter of said nanoporosity where said nanoparticles are located such that said nanoparticles are trapped within said porous matrix and occupy more than 5% and less than 100% of said porosity such that there is free volume available within said porosity.