Developing physical models of lithium-ion batteries for a more precise simulation of electrochemical e_ects and temperature influences outside the operation range

The aim of the project LIBERA was the development of realistic battery simulation models to depict the behaviour of battery cells under extreme loads near to a short-circuit with high currents. These conditions vary considerably from the design point of the lithium-ion batteries and were transferred into simulation models, which are able to locally resolve electrochemical behaviour of the battery cell. For that, the condition variables temperature, current density and state of charge were identified.
Therefore the project partner CADFEM first developed a basic physical model of lithium-ion batteries. In the next step the models were expanded by electrochemical effects and temperature influences outside of the usual working area. Technische Hochschule Ingolstadt (THI) developed special test benches and test methods to be able to perform the high current load tests in a safe way. The results of the THI measurements served for parameterisation and validation of the developed battery models.