Open-source tool for battery module simulation and design

Abstract

Electric and hybrid vehicles are two of the most promising solutions to meet the new emission requirements of the transportation sector. The energy storage system is their most critical component in terms of performance. Therefore, battery modeling plays an important role for designing and controlling battery modules. Up to now, the design of battery modules is conditioned by the use of expensive tools that involve long simulation times; in response to this, the present work introduces an open-source tool developed in Python to study the performance of battery modules and contribute to their design. To show the scope and use of the tool, a theoretical case study is presented. In particular, the effect of slight differences in cells behavior, due to manufacturing process or aging, is shown at the module level. A SOC difference of 2.5%, due to current imbalances, was obtained among the cells after discharge for a small battery module with new cells. This result points out the importance of accurate and fast module models to correctly predict the remaining travel range and the need for an online parameters identification procedure. In addition, the temperature distribution in the module along with the heat generated by the cells, also estimated by the tool, can be used for proper design and control of the battery cooling system.