Comparisons of Co–B alloys synthesized via different methods for secondary alkaline batteries

Cobalt borides were synthesized via chemical reduction method, ball milling method and electric arc method, and adopted as anode materials for secondary alkaline batteries. The crystal structures and BET surfaces of Co–B alloys were characterized and analyzed via X-ray diffraction (XRD) and nitrogen adsorption–desorption test, respectively. The electrochemical activities of Co–B samples were examined by cyclic voltammetry (CV) and charge–discharge test. It shows that the electrochemical performances of Co–B alloy synthesized via chemical reduction method are superior to those of Co–B alloys synthesized via the other methods, which result from its amorphous structure, large surface area, and intact activity centers. The initial discharge capacities of Co–B alloys synthesized via chemical reduction method, ball milling method and electric arc method are 301 mAh/g, 238 mAh/g and 214 mAh/g, respectively.