Novel sulphur-modified monolithic porous carbon-based material process for the preparation thereof and uses thereof in the storage and release of energy

• US 20120156567A1
• Filed: 11/11/2011
• Published: 06/21/2012
• Est. Priority Date: 11/23/2010
• Status: Active Grant

• Current Assignee: Hutchinson (Welltower, Inc.)
• Original Assignee: Hutchinson (Welltower, Inc.)
• Inventors: Sonntag, Philippe, Ayme-Perrot, David, Dieudonné, Marie, Pasquier, Anne-Caroline
• Granted Patent: US 8,778,230 B2
• Time in Patent Office: Days
• US Class Current: 429/231.8
• CPC Class Codes: C01B 32/00 Carbon; Compounds thereof C01B21/00, C01B23/00 take precedence; percarbonates C01B15/10; carbon black C09C1/48
• CPC Class Codes: C04B 2111/00844 for electronic applications
• CPC Class Codes: C04B 2111/00853 in electrochemical cells or batteries, e.g. fuel cells
• CPC Class Codes: C04B 35/52 based on carbon, e.g. graphite
• CPC Class Codes: C04B 38/0022 obtained by a chemical conversion or reaction other than those relating to the setting or hardening of cement-like material or to the formation of a sol or a gel, e.g. by carbonising or pyrolysing preformed cellular materials based on polymers, organo-metallic or organo-silicon precursors
• CPC Class Codes: C04B 38/0045 by a process involving the formation of a sol or a gel, e.g. sol-gel or precipitation processes
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/4535 applied as a solution, emulsion, dispersion or suspension
• CPC Class Codes: C04B 41/455 the coating or impregnating process including a chemical conversion or reaction
• CPC Class Codes: C04B 41/5097 Sulfur
• CPC Class Codes: C04B 41/85 with inorganic materials
• CPC Class Codes: H01G 11/34 characterised by carbonisation or activation of carbon
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 4/583 Carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

A subject-matter of the invention is a novel process for the preparation of sulphur-modified monolithic porous carbon-based materials by impregnation with a strong sulphur-based acid, the materials capable of being obtained according to this process and the use of these materials with improved supercapacitance properties to produce electrodes intended for energy storage systems.

Electrodes composed of sulphur-modified monolithic porous carbon-based materials according to the invention and lithium batteries and supercapacitors comprising such electrodes also form part of the invention.

Claims

1. Process for the preparation of a sulphur-modified monolithic porous carbon-based material, characterized in that it comprises at least the following stages:

(i) the drying of a gel comprising at least one hydrophilic polymer of polyhydroxybenzene/formaldehyde type,

(ii) the pyrolysis of the material obtained during stage (i),

(iii) the impregnation of the material resulting from stage (ii) with a strong sulphur-based acid,

(iv) the heat treatment at a temperature of between 300 and 500°

C., preferably between 350 and 500°

C., and more preferably still between 300 and 400°

C., of the sulphur-modified material obtained at the end of stage (iii),

the said process not comprising a hydrogenation stage.

2. Process according to claim 1, characterized in that the said gel additionally comprises at least one latex.

3. Process according to claim 2, characterized in that the said latex is a nitrogen-based latex, preferably chosen from nitrile rubbers.

4. Process according to one of claims 1 to 3, characterized in that the stage (i) of drying is carried out either by exchange of solvents and then drying in a supercritical CO₂ medium, or by convective drying under a gas stream or in a climate-controlled chamber at a controlled degree of humidity, or by lyophilization.

5. Process according to one of claims 1 to 4, characterized in that the stage (ii) of pyrolysis is carried out under a nitrogen atmosphere according to the following protocol:

a slow rise in temperature, at a rate of between 1 and 5°

C./min, up to a temperature of 400-500°

C., it being possible for this temperature to be maintained for an approximate period of time of one hour, followed by

a faster rise in temperature, at a rate of between 5 and 20°

C./min, up to a temperature of 800-1500°

C., it being possible for this temperature to be maintained for an approximate period of time of two hours.

6. Process according to one of claims 1 to 5, characterized in that the strong sulphur-based acid is an acid based on sulphur which is provided in the form of a solution of pH<

1.

7. Process according to one of claims 1 to 6, characterized in that the strong sulphur-based acid is chosen from sulphuric acid, oleum, chlorosulphonic acid and fluorosulphonic acid.

8. Process according to one of claims 1 to 7, characterized in that the said strong sulphur-based acid is a sulphuric acid solution having a concentration of between 0.5M and saturation, and preferably between 1M and saturation.

9. Process according to one of claims 1 to 8, characterized in that the stage (iv) of heat treatment is carried out for a period of time of between 1 minute and 12 hours, and preferably of less than or equal to 2 hours.

10. Sulphur-modified monolithic porous carbon-based material capable of being obtained according to the process of claims 1 to 9, characterized in that it comprises a surface atomic percentage of sulphur varying from 0.01 to 0.5%, and exhibiting a density of between 0.5 and 1.3.

11. Material according to claim 10, characterized in that it comprises a surface atomic percentage of sulphur varying from 0.1 to 0.5%, and a density of between 0.75 and 1.1.

12. Material according to claim 10 or claim 11, characterized in that it exhibits a pore volume varying from 0.4 to 1 cm³·

g<sup>−

1</sup>, and preferably from 0.4 to 0.75 cm³·

g<sup>−

1</sup>.

13. Material according to one of claims 10 to 12, characterized in that at least 10% of its pores have a diameter of between 2 and 50 nm.

14. Material according to one of claims 10 to 13, characterized in that it exhibits a specific surface of greater than or equal to 500 m²·

g<sup>−

1</sup>.

15. Material according to one of claims 10 to 14, characterized in that it exhibits a mean full capacitance by weight of greater than or equal to 140 F/g, measured in a 1M aqueous H₂SO₄ solution, or of greater than or equal to 120 F/g, measured in a 6M aqueous KOH solution.

16. Use of a sulphur-modified monolithic porous carbon-based material according to one of claims 10 to 15 to produce electrodes intended for supercapacitance energy storage systems.

17. Electrode characterized in that it is composed of a sulphur-modified monolithic porous carbon-based material as defined according to one of claims 10 to 15.

18. Supercapacitor characterized in that it comprises at least one electrode according to claim 17.

19. Lithium battery characterized in that it comprises at least one electrode according to claim 17.