Binder-free sulfur—carbon nanotube composite cathodes for rechargeable lithium—sulfur batteries and methods of making the same

• US 8,974,960 B2
• Filed: 12/22/2011
• Issued: 03/10/2015
• Est. Priority Date: 12/22/2011
• Status: Expired due to Fees

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Manthiram, Arumugam, Su, Yu-Sheng
• Primary Examiner(s): Cantelmo, Gregg
• Application Number:
  US13/335,514
• Publication Number:
  US 20130164626A1
• Time in Patent Office: 1,174 Days
• Field of Search: 429/231.8, 428/221, 977/742, 977/948
• US Class Current: 429/218.1
• CPC Class Codes: B82B 3/00 Manufacture or treatment of nanostructures by manipulation of individual atoms or molecules, or limited collections of atoms or molecules as discrete units
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 32/168 After-treatment
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/139 Processes of manufacture
• CPC Class Codes: H01M 4/1397 of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/58 of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component

Abstract

The present disclosure includes a sulfur-carbon nanotube composite comprising a sheet of carbon nanotubes and sulfur nucleated upon the carbon nanotubes, and methods for synthesizing the same. In some embodiments, the sulfur-carbon composite may further be binder-free and include a sheet of carbon nanotubes, rendering a binder and a current collector unnecessary. In other embodiments of the present disclosure, a cathode comprising the sulfur-carbon nanotube composite is disclosed. In additional embodiments of the present disclosure, batteries may include the cathodes described herein. Those batteries may achieve high rate capabilities.

Claims

1. A sulfur-carbon nanotube composite comprising:

a sheet of self-assembled, interwoven, multi-walled carbon nanotubes;

sulfur nucleated upon the carbon nanotubes in an amount of at least 45 weight % of the composite and configured to reversibly react with an alkali metal to form polysulfides.

2. The sulfur-carbon nanotube composite of claim 1, wherein the sheet of carbon nanotubes is configured to substantially prevent the dispersal of polysulfides away from the sheet.

3. A cathode comprising:

a sheet of self-assembled interwoven, multi-walled carbon nanotubes; and

sulfur nucleated upon the carbon nanotubes nanotubes in an amount of at least 45 weight % of the combination of carbon-nanotubes and sulfur and configured to reversibly react with an alkali metal to form polysulfides,

wherein the cathode is substantially free of any binder.

4. The cathode of claim 3, wherein the cathode does not comprise a current collector.

5. The cathode of claim 3, wherein the sheet of carbon nanotubes is configured to substantially prevent the dispersal of polysulfides away from the sheet.

6. The cathode of claim 3, wherein the sulfur nucleated upon the carbon nanotubes is present in an amount of at least 60 weight % of the combination of carbon-nanotubes and sulfur.

7. A battery comprising:

a cathode comprising;

a sheet of self-assembled interwoven, multi-walled carbon nanotubes; and

sulfur nucleated upon the carbon nanotubes in an amount of at least 45 weight % of the combination of carbon-nanotubes and sulfur and configured to reversibly react with an alkali metal to form polysulfides;

an anode comprising an alkali metal;

an electrolyte.

8. The battery of claim 7, wherein the battery is chargeable in less than ⅔

the theoretical charge time.

9. The battery of claim 7, wherein the cathode does not comprise a current collector.

10. The battery of claim 7, wherein the sheet of carbon nanotubes is configured to substantially prevent the dispersal of polysulfides away from the sheet.

11. The battery of claim 7, wherein the sulfur nucleated upon the carbon nanotubes is present in an amount of at least 60 weight % of the combination of carbon-nanotubes and sulfur.