BUS high current battery model

An empirical model for voltage and equivalent series resistance (ESR) has been developed for lead acid batteries used as a pulsed power source. During the design of the battery upgraded supply (BUS) for Eglin Air Force Base, the Center for Electromechanics at the University of Texas at Austin (CEM-UT) developed a model for the batteries to be used in this system. BUS is a 5 MA, 500 MJ inductive power supply charged by batteries for use as a railgun power supply. A series of tests was performed to determine the driving voltage and ESR of the batteries for discharge times from 2 to 10 s and current levels from 500 to 2500 A. A model for voltage and ESR was obtained from these tests. The methods used and sample data from the tests are presented. The main factors affecting battery voltage and ESR are discussed, and the models developed for the batteries tested are described. It is concluded that the proposed empirical model can be used to predict the performance of Pulsar batteries as long as the currents are around 500 to 2500 A and the timeframes are from 2 to 10 s