**6. Conclusions**

To reduce the electric loss in the connection of battery cells for electric vehicles, the joining process and the resulting transition resistance are essential. By introducing a model representing the joints' partial resistances, the current flow through the connection could be investigated. As a consequence, various joint geometries were investigated using a laser welding process to leverage and examine the observed edge current phenomenon. Naturally the current density along the material edges of the overlap, which are perpendicular to the current flow, was predominantly higher compared to the inner contact area. By measuring a *CQI* for each proposed connection, the influence of different weld seam geometries could be identified. Using double welds close to the edges of the overlapped materials yielded the investigations minimum *CQI* of about 0.52 and should hence be considered for manufactural purposes. The sheer increase of the welded contact area should be critically assessed, as it had a significantly smaller influence to the *CQI* and could even reduce the joint's conductivity.

**Author Contributions:** Idea, study design and laser welding were done by S.H. The development of the measurement system and measurements have been performed by S.K. The electrical modelling and theoretical background was contributed by C.Ü. A.O. contributed to the laser welding process and study design. A.G. and D.U.S. contributed to all parts. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
