Modeling of the charge-discharge behavior of a 12-V automotive lead-acid battery and comparison with measurement data

摘要

For the optimal design of the vehicle electric system, it is important to have a reliable modeling tool to predict the charge-discharge behavior of the automotive battery. In this work, a two-dimensional modeling was carried-out to predict the charge-discharge behaviors of a 12-V automotive lead-acid battery. The model accounted for electrochemical kinetics and ionic mass transfer in a battery cell. In order to validate the modeling, modeling results were compared with the measurement data of the charge-discharge behaviors of the lead-acid batteries having nominal capacities of 90Ah and 68Ah that are mounted on the automobiles manufactured by Hyundai Motor Company. The discharge behaviors were measured with four different discharge rates of C/3, C/5, C/10, and C/20 at five different operating temperatures of -20, 25, 40, 60, and 75℃. The batteries were charged with constant current of 30A until the charging voltage reached a predetermined value and then with the constant voltage. The discharge and charge curves from the measurements and modeling were in good agreement. Based on the modeling, the distributions of the electrical potentials of the solid and solution phases, the porosity of the electrodes, and the current density within the electrodes as well as the acid concentration can be predicted as a function of charge and discharge time.