Success Story: Two German Companies Revolutionize Battery Cell Production in the E-Mobility Sector

Partnership between Plasmatreat and Venjakob replaces costly film wrapping process

Local expertise from North-Rhine Westphalia (NRW) bundled, innovative solution developed for international battery production: Plasmatreat GmbH (Steinhagen) and Venjakob Maschinenbau GmbH & Co. KG (Rheda-Wiedenbrück) are now making battery production more efficient and reliable thanks to a newly developed process. For reliable electrical insulation, plasma-cleaned battery cells are given a special coating instead of a complex film wrapping. Battery manufacturers are benefiting from the proximity of the two companies, which are working together to simulate processes under realistic conditions and produce small batches.

The e-mobility sector is looking for solutions to further improve battery reliability and safety. One starting point for optimization is electrical insulation. Traditionally, battery cells, especially prismatic cells, are wrapped with a film. The process is costly, time-consuming and contains sources of errors. Now an innovative process is making battery production more efficient, faster and more reliable: the battery cells are coated with a special lacquer instead of foil. The companies Plasmatreat and Venjakob have combined their expertise.

Plasmatreat - Perfect lacquer adhesion through ultra-fine cleaning
Plasmatreat is the world leader in atmospheric plasma technology and has developed Openair-Plasma technology. In this case, it is used for ultra-fine cleaning of the bare battery cell and enables reliable, long-term stable lacquer application. The Openair-Plasma is precisely applied to the metal surface of the battery cells in a plasma treatment unit (PTU) at atmospheric pressure using simple compressed air and electricity through specially designed nozzles. Compared to conventional cleaning methods, the process is much more environmentally friendly, selective and inline capable. The surfaces of the battery cells are reliably cleaned of wafer-thin layers of dust and residual traces from the production process, such as oil or grease. This allows the protective coating to be applied without gaps. Long-term adhesion is achieved.

Venjakob – Contact-free coating, minimizing sources of error
The mechanical engineering company Venjakob, a specialist in coating lines, has developed a fully automated system for a continuous contact-free coating process. Battery cells in various formats are coated with a 100% UV coating after ultra-fine cleaning using Openair-Plasma. A specially designed tool carrier ensures that sensitive areas and the electrical poles of the battery cells are reliably protected from overspray. Since the process requires no gripping, turning or other handling, the risk of damage to the battery cells is minimized. The contact-free process also allows for higher production speeds. The immediate curing of the UV coating means that the cells can be processed directly. This speeds up the entire battery manufacturing process.

Successful alternative manufacturing process
Various analyses confirm the high efficiency of the innovative insulating coating, which achieves adhesion values in excess of 15 MPa in tensile shear tests. The two partners attribute the success of the project primarily to the fact that they matched each other in key areas. These include extensive technological expertise, uniformly high-quality standards, flexible adaptability to changing customer requirements, and intensive communication based on mutual trust. In this case, the joint customers also benefit from the close proximity, which has made it possible to demonstrate and evaluate ultra-fine cleaning and coating in a near-series process in Steinhagen and Rheda-Wiedenbrück.