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1. WO2007137795 - POROUS ELECTRICALLY CONDUCTIVE CARBON MATERIAL AND USES THEREOF

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Claims

1. A porous electrically conductive carbon material including graphene stacks (2) and having first and second pores (6, 8) in first and second different pore size ranges respectively, wherein said first pores (6) are of irregular shape in three dimensions, are interconnected to form transport passages through said carbon material and have sizes in the size range from lOμm to lOOnm, wherein said second pores (8) are defined between neighbouring graphene stacks (2), are of irregular shape in three dimensions, are interconnected, communicate directly or indirectly via other second pores with said first pores and have sizes in the size range from less than lOOnm to 3nm and wherein said graphene stacks defining said second pores form wall material between said first pores (6) .

2. A porous carbon material in accordance with claim 1 wherein a majority of said second pores (8) have sizes in the range from 50nm to 3nm, and particularly from 3nm to 8nm.

3. A porous carbon material in accordance with claim 1 or claim 2 wherein a majority of said first pores (6) have sizes in the range from 5μm to 500nm, and particularly in the range from 2μm to 500nm.

4. A porous carbon material in accordance with any one of the preceding claims wherein the total pore volume comprising micropores with a volume less than 3nm, the second pores in the size range from less than lOOnm to 3nm and the first pores in the size range from lOμm to lOOnm lies in the range from 0.1 to 1.0 cc/g.

5. A porous carbon material in accordance with claim 4 wherein said total pore volume lies in the range from 0.40cc/g to 0.65cc/g with the volume of second pores (8) lying in the range from 0.35cc/g to 0.55cc/g and the volume of the first pores lying in the range from 0.05cc/g to O. lcc/g.

6. A porous carbon material in accordance with any one of the preceding claims wherein the ratio of the total pore volume of the second pores (8) to the total pore volume of the first pores (6) lies in the range from 2 to 12.

7. A porous carbon material in accordance with any one of the preceding claims and having a BET surface in the range from 50m2 /g to 800 Vd2Ig, especially from 250 m2/g to 350 m2/g and particularly of around 350 m2/g.

8. A porous carbon material in accordance with any one of the preceding claims and having an H/ C atomic ratio in the range from 0.3 to 0.01 and preferably in the range from 0.2 to 0.075 and especially of about 0.1.

9. A porous carbon material in accordance with any one of the preceding claims 1 in which the carbon material has been heat treated to effect conversion to non-graphitic carbon with the required degree of order at a temperature in the range from 6000C to 100O0C.

10. A porous carbon material in accordance with any one of the preceding claims in which the carbon is present in the form of non- graphitic carbon comprising a plurality of randomly orientated gra- phene stacks having stack heights in the range from 2 to 30 nm and lateral extension values LA in the range from 2 to 8 nm, the gra- phene stacks either contacting one another or being separated by amorphous carbon usually distributed throughout the structure and present between the graphene stacks in a total amount relative to the graphene stacks material of less than 10% by weight.

11. A porous carbon material in accordance with any one of the preceding claims, wherein the carbon material is made by carbonizing a carbon monolith precursor having a porosity generating fugitive phase dispersed therein, said fugitive phase comprising particles in first and second size ranges, said first size range being from lOμm to 100 nm and said second size range being from less than 100 nm to 3nm, and subsequently removing said fugitive phase to form a porous carbon monolith.

12. A porous carbon material in accordance with claim 11, wherein said_ fugitive phase is SiO2 and is removed from said heat treated carbon monolith precursor by chemical dissolution.

13. A porous carbon material in accordance with claim 11, wherein said fugitive phase is polystyrene and is removed during carbonizing of the carbon monolith precursor by vaporisation.

14. A porous carbon material in accordance with one of the preceding claims, wherein the carbon material is made by manufacturing a mixture containing at least one carbon precursor and an organic polymer in an organic solvent,
by vaporizing the solvent until a viscous or highly viscous composition of a corresponding shaped body is obtained,
by shaping the viscous composition into a shaped body and by heating the composition of the shaped body to a temperature between 6000C and 10000C.

15. A porous carbon material in accordance with any one of the claims 11 to 14, wherein said carbon precursor is a naphthol solution.

16. A porous carbon material in accordance with any one of the claims 11 to 14, wherein said carbon precursor is mesophase pitch.

17. A porous carbon material in accordance with claim 14, wherein said organic polymer is polystyrene.

18. Use of a carbon material in accordance with any one of the preceding claims as an electrode in a lithium-ion battery.

19. Use of a carbon material in accordance with claim 18, wherein the carbon material is present in the form of a carbon monolith.

20. Use of a carbon material in accordance with claim 10, wherein the electrode is made by pasting a mixture of the carbon material and a binder on a metal foil.

21. Use in accordance with claim 20, wherein the ratio of the carbon material to the binder is approximately 9 to 1 by weight.

22. Use in accordance with claim 19 or claim 20, wherein the binder is poly (vinyl difluoride).

23. A lithium-ion battery having an electrode comprising a carbon material as specified in any one of the preceding claims.

24. An electrode for a lithium-ion battery comprising a carbon material as specified in any one of the preceding claims 1 to 22.

25. A porous carbon material in accordance with any one of the preceding claims 1 to 17 when loaded and/ or coated with a catalyst.

26. A porous carbon material in accordance with claim 25 wherein said catalyst is platinum (Pt).

27. A porous carbon material in accordance with claim 25 wherein it is loaded and/ or coated with ruthenium oxide before being loaded and/ or coated with platinum (Pt) as catalyst.

28. Use of a porous carbon material in accordance with any one of claims 25 to 27 in a fuel cell, in particular for the oxidation of methanol in a direct methanol fuel cell.

29. Use of a porous material in accordance with any one of the claims 1 to 17 as a support in a chemical, electrochemical, biological or physical device such as a detector, a reactor or a supercapacitor.