The assembly of the actual battery module, the so-called “stacking and welding”, places high demands on the engineering company and the production equipment in the automated manufacturing of battery systems. In addition to the quality and safety aspects, the so-called Overall Equipment Effectiveness (OEE) must also be kept in mind. The interlinking with upstream system parts can be implemented in various ways. The connection through driverless transport systems, so-called AGVs, promises high flexibility and reliability. It is also possible to link the systems directly. Buffer sections allow a smooth and standstill-free process in order to achieve the highest possible OEE.

PART 2 | Stacking and Welding: High demands on process reliability and quality

In the first production step of stacking and welding, the prepared individual cells are fed in and sorted according to their variant. The cells and end plates must first be aligned in the previously defined position and then pressed together. Depending on the product design, the side plates are coated with adhesive. The previous plasma treatment or laser cleaning to remove component contamination increases the bondability. Integrated camera systems and 3D scans for quality assurance ensure correct arrangement and flawless processing. After that, the side plates are also positioned and connected to one another using high-precision laser welding processes. In this step, online process and component monitoring is particularly important - process monitoring including recording of laser power and reflection as well as temperature monitoring during the lasering guarantee safe production. In order to enable flawless further processing, the component is measured in defined intermediate steps or after the assembly process has been completed.

For this section, it is essential to develop an average concept. "Thermal runaway" is recognized by thermal imaging camera systems. Affected components are ejected in locked boxes. These discharge options are integrated in all compression and welding stations. A discharge is also possible in downstream process steps or parts of the plant, if required.

A major difficulty in the “Stacking and Welding” production section is the combination and coordination of the individual processes in the smallest space. As a solution, the engineers at AKE technologies have developed an innovative concept for equalizing the individual processes, which includes inexpensive, flexible tools and component pick-ups.

The integration of a wide variety of component types is common on the assembly lines for module production. The variant management is simplified by a flexible design of the tools without the need for set-up processes.

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 3 | From the pre-assembly process to the integration into the battery module

COMING SOON:

• Module assembly - PART 4 | End of Line Testing & Module Finishing: Traceability as a decisive factor