Nanostructured electrode for energy storage device

1. An electrode comprising:

a current collector comprising:

a conductor layer having at least a first surface; and

elongated metal carbide nanostructures extending from the first surface; and

a carbonaceous energy storage media disposed on the first surface and in contact with the elongated metal carbide nanostructures wherein the elongated metal carbide nanostructures are electrical conductors configured to reduce intrinsic resistance of the electrode.

2. The electrode of claim 1 , wherein the current collector comprises a cover layer disposed on the first surface, and wherein the elongated metal carbide nanostructures extend through the cover layer.

3. The electrode of claim 1 , wherein the carbonaceous energy storage media comprises carbon nanotubes.

4. The electrode of claim 1 , wherein the carbonaceous energy storage media comprises a contact layer comprising carbon nanotubes in contact with the elongated metal carbide nanostructures extending from the first surface, and wherein the contact layer comprises a compressed layer of carbon nanotubes.

5. The electrode of claim 4 , wherein the contact layer comprises an aggregate of carbon nanotubes, wherein the aggregate of carbon nanotubes is a dried aggregate that is substantially free of any liquid.

6. The electrode of claim 5 , wherein the elongated metal carbide nanostructures extend through the contact layer.

7. The electrode of claim 5 , further comprising a first overlayer of carbonaceous material disposed on the contact layer.

8. The electrode of claim 7 , wherein the first overlayer has a thickness in a direction perpendicular the first surface that is greater than a thickness of the contact layer along the same dimension.

9. The electrode of claim 7 , wherein the contact layer has a thickness in a direction perpendicular the first surface of less than about 5 μm.

10. The electrode of claim 7 , wherein the contact layer has a thickness in a direction perpendicular the first surface of less than about 10 μm.

11. The electrode of claim 7 , wherein the first overlayer has a thickness in a direction perpendicular the first surface of in the range of about 10 μm to about 1,000 μm.

12. The electrode of claim 7 , wherein the first overlayer comprises carbon nanotubes.

13. The electrode of claim 7 , wherein no adhesion or bonding layer is disposed between the contact layer and the first overlayer and wherein the contact layer and the overlayer adhere through Van der Waals bonding between carbonaceous material in each layer.

14. The electrode of claim 1 , wherein the elongated metal carbide nanostructures comprise nanorods each having a radial thickness of less than 50 nm and a longitudinal length of greater than 500 nm.

15. An energy storage device comprising:

at least one electrode comprising:

a current collector comprising:

a conductor layer having at least a first surface; and

elongated metal carbide nanostructures extending from the first surface; and a carbonaceous energy storage media disposed on the first surface and in contact with the elongated metal carbide nanostructures wherein the elongated metal carbide nanostructures are electrical conductors configured to reduce intrinsic resistance of the electrode.

16. The energy storage device of claim 15 , wherein the current collector comprises a cover layer disposed on the first surface, and wherein the elongated metal carbide nanostructures extend through the cover layer.

17. The energy storage device of claim 15 , wherein the carbonaceous energy storage media comprises carbon nanotubes.

18. The energy storage device of claim 15 , wherein the carbonaceous energy storage media comprises a contact layer comprising carbon nanotubes in contact with the elongated metal carbide nanostructures extending from the first surface, and wherein the contact layer comprises a compressed layer of carbon nanotubes.

19. The energy storage device of claim 15 , comprising one of an ultracapacitor and a battery.