Patent ID: 7396494

Claim:
A method comprising: fabricating carbon fiber bundles from chopped carbon fibers; disposing the chopped carbon fibers in a mold; disposing an organic polymer into the mold; immersing the chopped carbon fibers in the organic polymer to form immersed chopped carbon fibers; pressurizing the immersed chopped carbon fibers in the mold; annealing the immersed chopped carbon fibers to form a carbon fiber block; slicing the carbon fiber block to form a plurality of carbon fiber sheets; each carbon fiber sheet having a longitudinal axis that is substantially parallel to respective carbon fibers in the bundle; intercalating an end face of a carbon fiber bundle in the carbon fiber sheet with nitrate ions; the intercalating being conducted by immersing the carbon fiber sheet into an electrolytic bath comprising nitric acid; illuminating the end face of the carbon fiber bundle with a pulse laser; and fibrillating the end face of the carbon fiber bundle to form a composite film.