Importance

Loading Importance Indicators...

Abstract

A method of producing a mercury-free corrosion resistant dendritic zinc alloy powder is provided. According to the method an electrolytic cell is prepared that contains an aqueous alkaline electrolyte with a preselected concentration of dissolved zinc cations and optionally the cations of one or more soluble inhibitor metals. The cell also contains a non-zinc adherent cathode, a first anode, and a second anode. The second anode comprises an inhibitor metal, the salts of which are only sparingly soluble in the alkaline electrolyte. For example, the second anode may comprise a minor anode of indium or bismuth interposed between the first or major anode and the cathode. A first voltage between the first anode and cathode is then applied to establish a desired cathode current density and the deposition of dendritic zinc and optional soluble inhibitor metals on the cathode. Concurrently a second voltage between the second anode and cathode is applied to establish a desired current density at the second anode and the simultaneous co-deposition of a desired concentration of the first inhibitor metal in the dendritic zinc being deposited on the cathode. Intermittently the deposited zinc alloy is removed from the cathode and homogenized into a plurality of dendritic zinc alloy particles. According to the method, mercury-free electrolytic zinc alloy powders with effective corrosion inhibiting concentrations of indium and/or bismuth either alone or in combination with other inhibitor metals can be produced. The corrosion resistant zinc alloy powders have a dendritic morphology that is advantageous for battery applications.

Loading the Abstract Image...

First Claim