Influence of pitch-based carbon foam current collectors on the electrochemical properties of lead acid battery negative electrodes

Pitch-based carbon foams prepared by a template method were used as negative current collectors to assemble flooded lead acid batteries, and the effect of the current collectors on the performance of the negative electrodes was investigated. Comparative galvanostatic charge–discharge tests show that the utilization efficiencies of the active material on the carbon foam negative current collector are 14% and 30% higher than those of the material on a lead grid one at 20 and 10 h discharge rates, respectively. Further EIS tests imply that there are also significant differences in the impedance spectra between the two electrodes. SEM images reveal that at the fully charged state, the particle size of the active material formed on the carbon foam current collector is much more uniform than that on the lead grid.