Application of Industrial Crystallization Model for Charge–Discharge Cycle of Lead–Acid Batteries at High Pressure

Abstract

The present study investigates the charge–discharge processes of a Planté lead–acid battery performed under atmospheric pressure and 10 MPa. The ampere-hour efficiency of the lead electrodes was substantially increased by the secondary formation of the Planté electrode, and the ampere-hour efficiency under 10 MPa was slightly higher than that under atmospheric pressure. The active PbSO₄ crystals on both electrodes were observed by SEM at different currents, and the morphology and crystal size distribution (CSD) were obtained. Active PbSO₄ crystals nucleated and grew during discharging; whereas, they disappeared during charging. This is similar to the crystal behavior during continuous crystallization in a battery. Therefore, a simple population balance model was used to express the CSD of PbSO₄ crystals on both electrodes. The CSD of both electrodes were similar at 10 MPa, but the CSD of the positive electrode was different from the CSD of the negative electrode. The current density on both electrodes was balanced under 10 MPa.