Synthesis of gamma monoclinic sulfur and sulfur batteries containing monoclinic sulfur

Patent metadata

Field	Value
Publication number	US-10991944-B2
Application number	US-202016900389-A
Country	US
Kind code	B2
Filing date	Jun 12, 2020
Priority date	Jan 14, 2019
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

The present invention relates to a method for making a novel cathode employing a monoclinic sulfur phase that enables a single plateau lithium-sulfur reaction in, for example, a carbonate electrolyte system. The cathode is applicable to a variety of other types of anodes. The method produces a cathode suitable for use in an electrode of a cell or battery by depositing monoclinic phase sulfur via vapor deposition onto a substrate in a sealed vapor deposition apparatus.

First claim

What is claimed is:

1. A method of depositing monoclinic sulfur on a substrate of a porous material, comprising steps of:
depositing monoclinic phase sulfur that is stable at a temperature below 80° C. via vapor deposition onto the substrate of the porous material in a sealed vapor deposition apparatus at a temperature sufficient to vaporize sulfur and for a time sufficient to provide the monoclinic phase sulfur, and
cooling the monoclinic phase sulfur deposited on the substrate of the porous material to a temperature of 0-50° C.,

wherein the substrate is positioned in the vapor deposition apparatus with a gab between a surface of a liquid sulfur reservoir and the substrate such that the substrate does not come into contact with liquid sulfur during the vapor deposition step.

2. The method of claim 1 , wherein the method provides a substrate with monoclinic sulfur deposited therein that is suitable for use as a cathode in an electrode of a cell or battery and a loading of the monoclinic phase sulfur on the substrate is at least 0.05 mg/cm 2 .

3. The method of claim 1 , wherein the depositing step is carried out in the sealed vapor deposition apparatus at a temperature of from 140° C. to 350° C.

4. The method of claim 1 , wherein the depositing step is carried out for a period of at least about 1 minute.

5. The method of claim 1 , wherein the cooling step is carried out by exposing the vapor deposition apparatus or the cathode to a temperature of less than 50° C.

6. The method of claim 5 , wherein the vapor deposition apparatus is cooled immediately upon completion of the depositing step.

7. The method of claim 1 , wherein the substrate of the porous material has a pore volume of 10-95% after deposition of the monoclinic phase sulfur on the substrate.

8. The method of claim 1 , wherein the substrate is conductive.

9. The method of claim 1 , wherein the substrate comprises carbon nanofibers.

10. The method of claim 9 , wherein the carbon nanofibers onto which the monoclinic phase sulfur is deposited are free-standing carbon nanofibers.

11. The method of claim 1 , wherein the monoclinic phase sulfur comprises a form of sulfur selected from the group consisting of monoclinic gamma phase sulfur; monoclinic sulfur that best matches monoclinic gamma phase sulfur using PDXL Version 2.8.4.0 Integrated Powder Diffraction Software; monoclinic gamma phase sulfur oriented in the k direction; and monoclinic sulfur that best matches monoclinic gamma phase sulfur oriented in the k direction using PDXL Version 2.8.4.0 Integrated Powder Diffraction Software.

12. The method of claim 1 , wherein the method provides a substrate with monoclinic sulfur deposited therein that is suitable for use as a cathode in an electrode of a cell or battery and a loading of the monoclinic phase sulfur on the substrate is at least 0.5 mg/cm 2 .

13. The method of claim 1 , wherein the depositing step is carried out in the sealed vapor deposition apparatus at a temperature of from 150° C. to 210° C.

14. The method of claim 1 , wherein the depositing step is carried out for a period of 10 to 30 hours.

15. The method of claim 1 , wherein the cooling step is carried out by exposing the vapor deposition apparatus or the cathode to a temperature of from about −20° C. to about 25° C.

16. The method of claim 1 , wherein the monoclinic phase sulfur comprises a form of sulfur selected from the group consisting of monoclinic gamma phase sulfur; monoclinic sulfur that best matches PDF Card No.: 00-013-0141 Quality:B for Rosickyite, monoclinic gamma phase sulfur, using PDXL Version 2 Integrated Powder Diffraction Software.

17. The method of claim 16 , wherein the substrate is non-conductive and the method provides a substrate with monoclinic sulfur deposited therein that is suitable for use as a cathode in an electrode of a cell or battery and a loading of the monoclinic phase sulfur on the substrate is at least 0.5 mg/cm 2 and the depositing step is carried out in the sealed vapor deposition apparatus at a temperature of from 150° C. to 210° C. for a period of 10 to 30 hours.

18. A method of depositing monoclinic sulfur on a substrate of a porous material, comprising steps of:
depositing monoclinic phase sulfur that is stable at a temperature below 80° C. via vapor deposition onto the substrate of the porous material in a sealed vapor deposition apparatus at a temperature sufficient to vaporize sulfur and for a time sufficient to provide the monoclinic phase sulfur, and
cooling the monoclinic phase sulfur deposited on the substrate of the porous material to a temperature of 0-50° C.,

wherein the substrate is non-conductive.

19. A method of depositing monoclinic sulfur on a substrate of a porous material, comprising steps of:
depositing monoclinic phase sulfur that is stable at a temperature below 80° C. via vapor deposition onto the substrate of the porous material in a sealed vapor deposition apparatus at a temperature sufficient to vaporize sulfur and for a time sufficient to provide the monoclinic phase sulfur, and
cooling the monoclinic phase sulfur deposited on the substrate of the porous material to a temperature of 0-50° C.,

wherein the method provides a substrate with monoclinic sulfur deposited therein that is suitable for use as a cathode in an electrode of a cell or battery and a loading of the monoclinic phase sulfur on the substrate is at least 0.5 mg/cm 2 and the depositing step is carried out in the sealed vapor deposition apparatus at a temperature of from 150° C. to 210° C. for a period of 10 to 30 hours.

20. The method of claim 19 , wherein the cooling step is carried out by exposing the vapor deposition apparatus or the cathode to a temperature of from about −20° C. to about 25° C. immediately upon completion of the depositing step.

Assignees

• Univ Drexel

Inventors

• Pai Rahul Nagesh
• Kalra Vibha

Classifications

• H01M10/054

  Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium · CPC title

• H01M10/0525

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

• H01M4/466

  Magnesium based · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M50/446

  Composite material consisting of a mixture of organic and inorganic materials · CPC title