Determination of the Contact Resistance of Planar Contacts: Electrically Conductive Adhesives in Battery Cell Connections
Philipp Jocher,
Michael K. Kick,
Manuel Rubio Gomez,
Adrian V. Himmelreich,
Alena Gruendl,
Edgar Hoover,
Michael F. Zaeh,
Andreas Jossen
Affiliations
Philipp Jocher
Chair of Electrical Energy Storage Technology (EES), Department of Energy and Process Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Arcisstr. 21, 80333 Munich, Germany
Michael K. Kick
Institute for Machine Tools and Industrial Management (iwb), Department of Mechanical Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Boltzmannstr. 15, 85748 Garching, Germany
Manuel Rubio Gomez
Chair of Electrical Energy Storage Technology (EES), Department of Energy and Process Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Arcisstr. 21, 80333 Munich, Germany
Adrian V. Himmelreich
Chair of Electrical Energy Storage Technology (EES), Department of Energy and Process Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Arcisstr. 21, 80333 Munich, Germany
Alena Gruendl
Institute for Machine Tools and Industrial Management (iwb), Department of Mechanical Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Boltzmannstr. 15, 85748 Garching, Germany
Edgar Hoover
Chair of Electrical Energy Storage Technology (EES), Department of Energy and Process Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Arcisstr. 21, 80333 Munich, Germany
Michael F. Zaeh
Institute for Machine Tools and Industrial Management (iwb), Department of Mechanical Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Boltzmannstr. 15, 85748 Garching, Germany
Andreas Jossen
Chair of Electrical Energy Storage Technology (EES), Department of Energy and Process Engineering, TUM School of Engineering and Design, Technical University of Munich (TUM), Arcisstr. 21, 80333 Munich, Germany
This study presents a method to analyze the electrical resistance of planar contacts. The method can determine whether the contact resistance of the joint exhibits linear or non-linear behavior. By analyzing the current distribution over a planar contact, it can be determined whether an area-based contact resistance is justified or if other parameters define the contact resistance. Additionally, a quantitative evaluation of the factors that affect the measurement accuracy, including the positioning, the measurement equipment used, and the influence of the current injection on the sense pin was conducted. Based on these findings, the electrical contact resistance and the mechanical ultimate tensile force of a silver-filled epoxy-based adhesive are analyzed and discussed. The layer thickness and the lap joint length were varied. Overall, the investigated adhesive shows a low contact resistance and high mechanical strength of the same magnitude as that of well-established joining techniques, such as welding, press connections, and soldering. In addition to evaluating the mechanical and electrical properties, the electric conductive adhesive underwent an economic assessment. This analysis revealed that the material costs of the adhesive significantly contribute to the overall connection costs. Consequently, the effective costs in mass production are higher than those associated with laser beam welding.
