JoiFlo

Experimental and numerical analysis of the flow behaviour of highly viscous thermal conductive materials in the manufacturing process

For the storage of electrical energy, high-voltage battery modules are used, which are integrated into battery housings in the vehicle floor. Ensuring the optimal operating temperature of the battery cells is of high priority. For this reason, battery housings are equipped with Thermal Management Systems (TMS), which must thermally coupled to the battery modules. This coupling is often realized through the use of thermal interface materials (TIM). The joining process of the battery module and the battery housing bottom, in which the TMS is integrated in current concepts, poses new challenges in the design of the joining process. Within the project, experimental methods and numerical modeling strategies are being developed to investigate the flow behavior of the TIM. In experimental work, the TIM is characterized and tested in crush tests under realistic conditions. Reaction forces and optical evaluation methods are used for validation. The numerical investigations for predicting the flow behavior and joining forces rely, among other things, on the arbitrary Lagrange-Eulerian (ALE) method. The flow behavior of TIM can be very well represented with this method. Further work focuses on the precise prediction of the joining forces to evaluate the stresses on the battery cells and the deformations of the battery housing for optimizing the joining processes in practice.