Framework for lead electrodes for lead accumulators - consists of non-conducting porous plastic strip, which is activated, chemically copper-plated, cut to size and electroplated with lead

摘要

Framework (I) for the Pb electrodes of a lead accumulator (II) is based on a strip of non-conducting plastic material (III) with 60-95% porosity which is chemically copper-plated after an activation process, cut to the length and/or breadth of the electrode and reinforced later by electroplating with a layer of lead. Process for prodn. of (I) comprises activating the surface of (III) with a HCl-contg. soln. based on Pd/Sn, removing excess activating soln. from surface and pores, chemically copper-plating the surface, removing excess plating soln., cutting to size, electroplating with lead and cleaning to remove residual electrolytes. (III) is non-woven fabric, needled felt or open-pore foam, based on PE or PP fibre or polyurethane; layer of Cu is 0.2-1 micron thick and layer of Pb is 3-8 microns thick. ADVANTAGE - The invention provides a framework (grid) in which the active material can be properly proportioned; accumulators contg. electrodes based on (I) are able to withstand a greater no. of charge/discharge cycles (w.r.t. prior-art grids), giving better capacity and better long-term performance.