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A multicell assembly is constituted by alternately stacking two types of pre-assembled elements: a bipolar electrode holding subassembly and a membrane holding subassembly. The alternate stack of elements is piled over a bottom end element and the stack is terminated by placing over the last membran

A multicell assembly is constituted by alternately stacking two types of pre-assembled elements: a bipolar electrode holding subassembly and a membrane holding subassembly. The alternate stack of elements is piled over a bottom end element and the stack is terminated by placing over the last membrane holding element a top end electrode element. Each bipolar plate electrode holding element and each ion exchange membrane separator holding element includes a substantially similar rectangular frame piece, made of an electrically nonconductive and chemically resistant material, typically of molded plastic material, having on its upper (assembly) face grooves for receiving O-ring type gasket means, and having through holes and recesses in coordinated locations disposed along two opposite sides of the rectangular frame forming, upon completion of the assembling, ducts for the separate circulation of the negative electrolyte and of the positive electrolyte through all the negative electrolyte flow chambers and all positive electrolyte flow chambers, respectively, in cascade.

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A multicell assembly is constituted by alternately stacking two types of pre-assembled elements: a bipolar electrode holding subassembly and a membrane holding subassembly. The alternate stack of elements is piled over a bottom end element and the stack is terminated by placing over the last membran

A multicell assembly is constituted by alternately stacking two types of pre-assembled elements: a bipolar electrode holding subassembly and a membrane holding subassembly. The alternate stack of elements is piled over a bottom end element and the stack is terminated by placing over the last membrane holding element a top end electrode element. Each bipolar plate electrode holding element and each ion exchange membrane separator holding element includes a substantially similar rectangular frame piece, made of an electrically nonconductive and chemically resistant material, typically of molded plastic material, having on its upper (assembly) face grooves for receiving O-ring type gasket means, and having through holes and recesses in coordinated locations disposed along two opposite sides of the rectangular frame forming, upon completion of the assembling, ducts for the separate circulation of the negative electrolyte and of the positive electrolyte through all the negative electrolyte flow chambers and all positive electrolyte flow chambers, respectively, in cascade. cathode is in physical contact with a metal current collector, the improvement comprising: said metal current collector comprising steel preplated with nickel, at least a portion thereof, being coated with a coating comprising a layer of cobalt (the cobalt layer) and a layer comprising carbon over the cobalt layer, wherein said layer comprising cobalt is applied over said nickel layer and the layer comprising carbon is applied over said cobalt layer, wherein said metal current collector is selected from the group consisting of said metal casing, a wire mesh, a metal foil, a metal sheet, metallic fibers, and metallic particles. 13. The cell of claim 12 wherein the inside surface of said steel casing is preplated with a layer of nickel and said layer comprising cobalt (the cobalt layer) is applied over said nickel layer and the layer comprising carbon is applied over said cobalt layer. 14. The cell of claim 13 wherein said cell is an alkaline cell comprising an anode comprising zinc, a cathode comprising manganese dioxide and an electrolyte comprising potassium hydroxide and said cathode contacts the inside surface of said metal casing. 15. The cell of claim 13 wherein said nickel and cobalt layers are applied to the inside surface of said metal casing by electrodeposition. 16. The cell of claim 15 wherein said layer comprising nickel and said layer comprising cobalt on said steel are subjected to heat treatment of between about 580 and 710° C. before said coating comprising carbon is applied over said cobalt. 17. The cell of claim 13 wherein the layer comprising carbon is formed by coating a dispersion comprising particulate carbon, binder and solvent carrier onto said cobalt layer and allowing the solvent carrier to evaporate. 18. The cell of claim 17 wherein the carbon in said dispersion comprises particulate graphite. 19. The cell of claim 13 wherein said layer comprising cobalt has a thickness between about 0.01×10-6and 1.0×10-6meters. 20. The cell of claim 13 wherein said layer comprising carbon has a thickness between about 0.0025 and 0.076 mm (dry basis).