|
Foam lead, as an important foam metal, has unique three dimensional reticulated structures. It is widely applied in batteries industry, because of its excellent high porosity and high specific surface area.This paper used polyurethane foam as substrate to prepare porous lead, which included degreasing process, roughening process, conductive treatment and copper and lead electrodeposition.The organic solvent degreasing and alkaline degreasing were combined as the degreasing process firstly. Secondly, the roughening of polyurethane foam was studied. Finally, electric pastern was smeared on polyurethane foam to make it electrical conductive.Based on Hull Cell test, sulfate system was chosed as the electroplating solution system for copper electrodeposition on polyurethane foam. The additives, which influence the prcocess of electroplating, were also examined. The results showed that adding both NaCl and OP emulsifying agent would get luster plating layer. Then the effects of solution composition, temperature, the cathodic current density, the interelectrode distance, and time on the current efficiency and cell voltage were carried out. The optimum experimental conditions were obtained as:CuSO4 180g/L, H2SO4 54g/L, NaCl 0.6g/L, OP emulsifying agent 0.4 mL/L, polar distance 3.5 cm, cathode electric current density 3.0 A/dm2, temperature 25℃and galvanization time 35 min. Under these conditions, the current efficiency was high with low voltage. At the same time, the copper plating layer presented good toughness and luster plating.Lead electrodeposition on copper plating layer was investigated. The effects including solution composition, the cathodic current density, temperature, time on the current efficiency, cell voltage and the morphology of foam lead were tested. The optimum experiment conditions were obtained as:Pb2+ 115g/L, dissociated HBF4 45g/L, boric acid saturation, additive 0.5g/L, cathode electric current density 3.0 A/dm2, plating temperature 25℃, and galvanization time 50 min. Under these conditions, the current efficiency was high with low cell voltage. At the same time, the foam lead presents three dimensional reticulated structure, high porosity, good toughness and luster plating layer.
|