High-specific surface area, three-dimensional reticulated electrodes for deep cycle lead-acid batteries

Power Technology Inc. has developed two types of proprietary reticulated, high specific surface area (⟩ 1000 m² m^-3) current collectors for lead-acid batteries manufactured by casting and plating, respectively. The comparative performance of the reticulated and standard grid-type current collectors was studied by single-cell battery testing and scanning electron microscopy (SEM). The electrochemical utilization efficiency of the positive active mass (PAM) in flooded cells equipped with 25 - 30 pores per inch (ppi) reticulated collectors was up to 55% higher than for a grid battery at 3 h discharge rate. These results were attributed to differences in PAM morphology induced by the current collector design, as shown by SEM micrographs. The reticulated battery with Pb-Sn alloy current collectors subjected to daily cycling composed of continuous 19 h float charge at 2.35 V/cell followed by a 5 hour discharge, exhibited a capacity loss of less than 10% in 30 days