Abstract: The present invention relates to carbon-carbon composite material comprising a carbonaceous carrier and nanosize carbon structures (e.g. CNT or CNF), wherein the nanosize carbon structures are grown on the carbonaceous carrier. The carrier may be porous, as in activated carbon or consists of carbon black particles. In accordance with the invention, nanocarbon growth in the pores of porous carriers can be realized. The process for the manufacture of a this carbon-carbon-composite material comprises the steps of treating a carbonaceous carrier material with a metal-containing catalyst material, said metal being capable of forming nanosize carbon structures, and growing nanosize carbon structures by means of a CVD (chemical vapour deposition) method on the treated carrier in a gas atmosphere comprising a carbon-containing gas, followed by an optional surface modification step.