Electrode for a rechargeable electrochemical cell and method and apparatus for making same

A process for manufacturing an electrode for a rechargeable electrochemical cell by electrodepositing a metal on the surfaces of a continuous metallic strip, said process comprising:

• providing an etchant tank containing an etchant for removing contaminants from said surfaces of said continuous metallic strip;
• passing said continuous strip through said etchant to effect removal of said contaminants from said surfaces of said metallic strip and into said etchant;
• providing an electrodeposition tank containing an electrolytic bath containing ions of the metal to be deposited;
• immersing in said electrolytic bath a positively polarized electrode comprising the metal to be deposited on said metallic strip;
• negatively polarizing said metallic strip;
• passing said metallic strip while negatively polarized through said tank and said electrolytic bath to effect deposition of said metal on said metallic strip, said electrodeposition step effected after said contaminant removal step;
• providing means for removing said contaminants from said etchant;
• and
• providing means for continuously recirculating said etchant between said etchant tank and said contaminant removal means.

A process for manufacturing an electrode for a rechargeable electrochemical cell containing an electrode by electrodepositing a metal on the surfaces of a continuous metallic strip, said process comprising the steps of:

• providing a first tank containing a first electrolytic bath containing ions of the metal to be deposited;
• immersing in said first electrolytic bath a positively polarized electrode comprising the metal to be deposited on said metallic strip;
• passing said continuous metallic strip into, through and out of said first electrolytic bath;
• simultaneously negatively polarizing said continuous metallic strip at a first location proximate where said strip passes into said first electrolytic bath and at a second location disposed after said continuous strip passes out of said electrolytic bath whereby the strip is negatively polarized while passing through said electrolytic bath and the deposition of said metal on said continuous metal strip is effected by said negative polarization of said strip at each of said first and second locations;
• and
• compacting said metallic strip with said metal deposited thereon at a third location disposed between said first and second locations.

A process for manufacturing an electrode for a rechargeable electrochemical cell containing an electrolyte by electrodepositing a metal on the surfaces of a continuous metallic strip, said process comprising the steps of:

• providing an electrodeposition tank containing a first electrolytic bath containing ions of the metal to be deposited;
• immersing in said electrolytic bath a positively polarized electrode comprising the metal to be deposited on said metallic strip;
• negatively polarizing said metallic strip;
• passing said metallic strip while negatively polarized through said tank and through said electrolytic bath to effect deposition of said metal on said metallic strip;
• compacting said deposited metal on said metallic strip;
• and thereafter
• coating said compacted deposited metal on said metallic strip with a non-conductive material permeable to said cell electrolyte and adapted to prevent migration of said deposited metal away from said metallic strip during discharging and charging of said rechargeable electrochemical cell.

A process for manufacturing an electrode for a rechargeable electrochemical cell containing an electrolyte, said process comprising the steps of:

• providing an electrically conductive metallic substrate;
• adhering a chemically active material to said substrate, said active material adapted to oxidize and reduce during charging and discharging of said cell;
• and then
• coating said active material with a thin layer of a polyvinylalcohol permeable to said cell electrolyte and adapted to prevent migration of said active material away from said metallic substrate during discharging and charging of said rechargeable electrochemical cell.

An electrode made by a process of electrodepositing a metal on the surface of a continuous metallic strip, said process comprising the steps of:

• providing a first tank containing an etchant for removing contaminants from said surface of said continuous metallic strip;
• passing said continuous metallic strip while negatively polarized through said etchant tank prior to passing said metallic strip through a first electrolytic bath to remove said contaminants on said surfaces of said metallic strip prior to said deposition step;
• providing a second tank containing an electrolytic bath which contains ions of the metal to be deposited;
• immersing in said first electrolytic bath a positively polarized electrode comprising the metal to be depoisted on said metallic strip;
• negatively polarizing said metallic strip;
• passing said metallic strip while negatively polarized through said second tank and through said first electrolytic bath to effect deposition of said metal on said metallic strip;
• providing a third tank containing a second electrolytic bath;
• immersing in said second electrolytic bath a second negatively polarized electrode;
• positively polarizing said metallic strip containing said deposited metal after emergence from said second tank, and
• passing said positively polarized metallic strip containing said deposited metal through said second electrolytic bath to effect oxidation of said deposited metal.