Nickel hydroxide/carbonate was chosen as the precursor to synthesize nickel nanopowders via an RF plasma-assisted hydrogen reduction route. Thermodynamic analysis revealed that the reaction could take place spontaneously. XRD patterns showed that metallic nickel powders could be obtained within the limited residence time. FESEM images indicated that the products consisted of well-dispersed spheres with an average diameter of about 60-100 nm. The obtained nickel powders exhibited high tap density. The use of nickel hydroxide/carbonate as the precursor guaranteed the products of high purity and the processing of environmental safety. The present plasma-assisted hydrogen reduction of nickel hydroxide/carbonate is an ideal route for large-scale synthesis of well-dispersed metallic nickel nanospheres used as electrode materials. (C) 2009 Elsevier B.V. All rights reserved.