Patent ID: 7993508

Claim:
A method for forming a coated casing for an electrochemical cell, comprising the steps of: providing an electrode casing comprising a metal substrate having an interior surface and an exterior surface and comprising a copper layer on the interior surface of the substrate; plating a first metal layer with a plating solution on at least the exterior surface of the substrate that is adapted to be exposed to the atmosphere when assembled in an electrochemical cell utilizing a first current density; and changing the first current density to a second different current density while the electrode casing is in contact with the plating solution and plating a second metal layer on the first plated layer; wherein: the first current density of the plating ranges from 10 to 1,076 amps per square meter, and wherein the second current density of the plating ranges from 1.0 to 27.0 amps per square meter with the proviso that the second current density is lower than the first current density; and the second plated layer has a higher weight percentage of tin and a lower weight percentage of copper compared to the first plated layer, and wherein the first and second plated layers each, independently, comprise copper, tin and zinc.