PEM Publishes Battery Module and Pack Production Guide

31/10/2023

The Chair of Production Engineering of E-Mobility Components (PEM) of RWTH Aachen University, together with the German Engineering Federation VDMA, has published a guide to processes in the production of battery modules and battery packs. The document, which is available in German and English, looks at developments and opportunities in industrial battery production as well as trends at the system level on 28 pages each and is available as a free download.

  Graphic of PEM's new production guidelines on battery modules and packs Copyright: © PEM of RWTH Aachen University

Reducing components and increasing energy density

"The classic 'cell-to-module-to-pack' architectures have great potential for improvement in terms of energy density, safety, durability, and production costs," says Professor Heiner Heimes, battery expert and member of PEM's institute management. "Future designs, as a 'cell-to-pack' or 'cell-to-chassis' approach, will rely on integrating cells either directly into the battery pack or directly into the chassis to reduce components and increase energy density."

In-house production outpaces purchasing

According to the guide, battery manufacturers will also produce each component themselves much more frequently in the near future, instead of buying them in as they have in the past. Current forecasts predict that in-house production of battery cells will increase from nine to 60 percent between 2020 and the period after 2024. In the same period, in-house production of battery modules and battery packs is expected to grow from 43 and 68 percent respectively to 80 percent in each case.

"Production line concepts in the future will be highly automated and yet very flexible. In this context, integrated buffer and rework stations are going to avoid potential downtime and decouple the time-consuming, complex assembly process."

The new guide explains module production from pouch as well as cylindrical and prismatic cells, from begin-of-line testing and stacking as well as plugging of the cells, through assembly of the battery management system and tab contacting using various welding processes, to final assembly. The necessary investments for machinery and equipment are also quantified for all key production processes. With regard to pack production, the authors discuss various cooling systems, sealing, leak testing, and charging as well as end-of-line testing. "Production line concepts in the future will be highly automated and yet very flexible," Heimes says. "In this context, integrated buffer and rework stations are going to avoid potential downtime and decouple the time-consuming, complex assembly process." Eventually, the guide provides an overview of potential hazards and corresponding safety measures.

Free download online

The "Production Process of Battery Modules and Battery Packs" guide is available as a free download in the "Electric Mobility Guides" section (see "Battery").