Failure Mode Based Design and Optimization of the Electrode Packaging Process for Large Scale Battery Cells

The increasing demand of electric vehicles and thus Lithium-Ion batteries results in a multitude of challenges in production technology. The cost-effectiveness, reproducibility, performance and safety requirements of large scale batteries for automotive applications are very high. At the same time the production processes are complex and have many uncertainties, namely how single parameters influence the specific values of the battery performance. Therefore, this article focuses on the design and optimization of production processes of large scale batteries using an established FMEA approach. This method is applied to the electrode packaging process, which constitutes a crucial production step, as the anode and cathode material is assembled to create a multi-layer cell. Based on a failure mode ranking, two categories of essential failure are considered in detail. First the positioning error of the electrode foils and following this the multi-layer handling during the process. Here, an algorithm to simulate the stacking error is presented and a sensor concept to detect multi gripped layers during the handling by a gripper integrated eddy current sensor is introduced.