Electrochemical Investigation of the Effect of Activated Coconut Shells in the Negative Plate of Lead Carbon Battery

The addition of certain types of carbon or graphite to the negative electrode paste mix of lead acid batteries has been reported to substantially slow down the capacity limiting accumulation of insoluble lead sulfate. The resulting lead carbon battery provides improved capacity and cycle life. This report presents the results obtained from recycling of some used lead acid cells into lead carbon battery negative electrodes through the addition of activated coconut shells mixed with graphite powder. Lead metal pieces and sulfated plate materials were obtained from used batteries. The lead pieces were melted and casted to form new grids. The plate materials were desulfurized and calcined to generate the lead oxide used for the new plates. Five new negative plates (30 mm2) composed of the carbon in the proportions (0, 2, 4, 6, 8) % by volume to the PbO contents were prepared. The plates were cured at 60 0C in high humidity for 12 hrs. and formed at 5 mA/cm2 for 12 hrs. Cyclic Voltammetry tests implemented with a Gamry 600+ Potentiostat indicated progressive increase in discharge current output with increase in the content of the electroactive carbon up to 4% carbon loading. Keywords: Lead Carbon battery, Desulfurization, Cyclic Voltammetry, Potentiostat. DOI: 10.7176/JNSR/9-20-08 Publication date:October 31st 201