Methane pyrolysis using plasma has recently attracted considerable attention. This method is eco-friendly and produces hydrogen and solid carbon black without producing carbon dioxide. However, it requires high energy to generate the plasma, making it economically ineffective. However, its economic feasibility can be secured using the by-products generated from methane pyrolysis as high -value materials. In this study, methane pyrolysis via thermal plasma and annealing was performed at 500-1,000 circle C to improve the properties of the by-products. The synthesized carbon black was nano -sized with an amorphous structure and its performance as a conductive material in batteries was analyzed. As a result, the specific surface area and electrical conductivity were improved to 45.87 m2/g and 6.5 S/cm, respectively, when carbon black was annealed at 1,000 circle C. Moreover, when used as a battery conductive material, the capacity was measured to be 320 mAh/g, which is comparable to that of Super -P, a commercial material. Finally, the annealing of carbon black by methane pyrolysis confirmed that its properties are similar to those of commercial carbon black and it could be applied as a conductive material for batteries.