Process for the manufacture of metallic foams

The process for manufacturing nickel foam, electrode current collector which is used on a large scale in alkaline rechargeable batteries, includes four main steps :
• conductive activation, by deposition of a conductive material onto a polyurethane foam,
• electro-deposition of nickel on the conductive foam,
• burning treatment for removing the polyurethane foam and annealing nickel,
• deoxidization and annealing treatment of the nickel structure.

The SCPS’ Team, thanks to his background in the industrial production of nickel foam during the 80s, has introduced a new conductive activation process based on the use of a conductive polymer which renders the polyurethane foam conductive.

This innovative process makes possible the electro-deposition of copper for a mass production of copper foam.

On the contrary of other activation technologies, which require to treat a band of polyurethane foam, the SCPS’ process allows to use cylinders of foam, which are coated by percolating the chemicals dissolved in water solutions, through their entire volume.

SCPS’ Activation is made at room temperature and room pressure. No organic solvents are used during this step.

After deposition of the conductive polymer, the foam is peeled to form a band before the electroplating of metal.

Advantages of the SCPS’ process :
• reduction of the production cost : low cost equipment and consumables, high productivity of the chemical reactors used for the conductive activation, electro-deposition of metal at higher speed during the second step (due to high efficiency of the activation).
• electro-deposition of nickel, copper, alloys, … thanks to the high hydrogen over-potential of the conductive polymer (electro-deposition of metal at low pH), and to its good thermal stability,
• no shape modification of the polyurethane foam (activation is made on foam blocks, and not on bands).