Abstract: A composite electrode structure and methods of making and using thereof are disclosed. The structure has a metal substrate with a metal oxide layer. The average thickness of the metal oxide layer is less than 150 nm, and comprises at least a first metal and a second metal, wherein the first metal and the second metal are different elements. A plurality of carbon nanotubes is disposed on a first surface of the metal oxide layer. At least a portion of the carbon nanotubes are disposed such that one end of the carbon nanotube is positioned at least 5 nm below the surface of the metal oxide layer.

Abstract: Embodiments of the present invention are directed to an energy storage device and a method for manufacturing the energy storage device. The method includes accessing a metal substrate and forming plurality of carbon nanotubes (CNTs) directly on a metal substrate. The method further includes removing substantially all amorphous carbon from said plurality of CNTs and coupling the plurality of CNTs to an electrolytic separator.

Abstract: Provided herein are novel electrodes for use, such as, for example, in electrochemical energy storage systems (i.e., Li-ion secondary batteries), fuel cells, secondary batteries based on hydrogen storage and ultracapacitors. The electrodes include carbon nanotubes attached to metal foil. In some embodiments, an ultracapacitor device is provided. The ultracapacitor device contains, inter alia, the novel electrodes described herein. In still other embodiments, a method of synthesizing the electrodes described herein is provided. Carbon nanotubes are deposited on a metal foil and amorphous carbon is removed.