Structural and electrochemical characterization of mechanochemically synthesized calcium zincate as rechargeable anodic materials

Hydrated calcium zincate was synthesized by mechanical ball milling of ZnO and Ca(OH)(2) in water at room temperature. The structural and electrochemical properties of this material used as rechargeable anodic material were examined by microelectrode voltammetry, charge-discharge measurements and structural analysis. The results showed that during mechanical milling, ZnO, Ca(OH)(2) and H2O reacted rapidly to form Ca[Zn(OH)(3)](2).2H(2)O which was subsequently transformed to a stable structure CaZn2(OH)(6).2H(2)O. Since this composite oxide has lower solubility in KOH solution (<35 wt %) and better electrochemical reversibility than ZnO-based negative materials, the zinc anodes using this material can overcome the problems of shape changes and dendritc formation, and therefore exhibit improved cycling life.