Abstract: This paper proposes a multiphysical model combining the equivalent circuit and physicochemical models to describe the start-stop cycle of a lead-acid battery. The cyclic charging and discharging processes that occur inside the battery were numerically simulated. The aging phenomenon, corrosion of the positive grid plate, sulfation of the negative electrode, and water loss caused by the escape of hydrogen and oxygen were considered to occur during the start-stop cycles. The battery capacity decay curve was predicted, and the changes in the concentration of sulfuric acid inside the battery were numerically analyzed. The accuracy of the model was verified by the good agreement between the simulation results and experimental data. This physicochemical model may help reduce experimental costs and provide support for battery research and development.

Key words: lead-acid battery, physicochemical model, numerical simulation, start-stop cycle