Numerous pre-assembly processes are necessary when assembling the complete battery module. The so-called cell contacting system (CCS) must also be installed in advance. CCS are responsible for interconnecting the individual battery cells in the battery module. They differ in numerous features. Depending on the vehicle design and the requirements of the OEMs, there are different arrangements of the cells according to the space available in the vehicle, a parallel or series connection is possible. The cells are put together to form single or double modules and are suitable for use in storage systems in hybrid vehicles (HEV / PHEV), in purely electric vehicles (BEV) or in the non-automotive sector.

PART 3 | The cell contacting system: from the pre-assembly process to integration into the battery module

The pre-assembly of the cell contacting system

The pre-assembly of the cell contacting system takes place in a highly automated process on upstream production lines. The pre-assembly lines are either directly connected to the final assembly of the battery modules or are designed as an independent plant section. Depending on the concept, after the automatic supply of cell connectors and current taps, the basic bodies of the CCS are equipped with voltage taps and temperature sensors. The pre-assembled cell connectors are implemented in the CCS carrier part. Ultrasonic or hot caulking processes provide the optimum solution for connecting the carrier parts, which serve to protect the cell connectors and complete the individual components to form the finished cell contacting system. After component marking for traceability, the production data is transferred to the MES (Manufacturing Execution System) and the cell contacting systems are output from the system.

Integration of the cell contacting system into the battery module

The interlinking of the pre-assembly line for cell contact systems with the battery assembly is implemented differently depending on the production concept. Automated guided vehicles (AGV) are suitable for the autonomous connection of the system lines. Output in trays or pallets can also be implemented; alternatively, the CCS are transferred directly to the downstream module assembly via buffer sections. In the welding cell of the assembly line for battery modules, the cell connectors are fixed to the cell terminals using hold-down masks and the zero gap required for the process is ensured. The pre-assembled CCS is then connected to the terminals of the cell stack using laser welding processes. In addition, depending on the component design, voltage taps are welded for subsequent connection of the CSC (Cell Supervision Circuits).

Intelligent data management for tracing production data

To meet process and component safety requirements for sensitive components, intelligent data management including traceability is integrated here. Complete data acquisition and process monitoring takes place during production. Complete data acquisition and process monitoring takes place during production. This makes it possible to trace individual parts that are relevant to safety. This data is transmitted to a higher-level production control system in the customer's plant.

Further parts from the series "Module assembly":

• Module assembly - PART 1 | Preparation processes for the assembly of battery systems with prismatic cells
• Module assembly - PART 2 | Stacking and Welding: High demands on process reliability and quality
• Module assembly - PART 4 | End of Line Testing Guarantees Flawless Processing in Battery Module Production