A method for making a battery electrode is provided. A carbon nanotube material is provided. The carbon nanotube material is placed into a furnace containing carbon dioxide. The furnace is heated to a temperature about 800° C. to about 950° C., and the carbon nanotube material is oxidized. The oxidized carbon nanotube material is dispersed in a first solution to form a carbon nanotube suspension. An active material is ultrasonically dispersed in a second organic solvent to form an active material dispersion. The carbon nanotube suspension is mixed with the active material dispersion to form a second solution. The second solution is stirred by ultrasonic means and dried after filtering.