Revolutionizing Battery Production: Digitalized and Sustainable

The evolution of storage systems plays a crucial role in the ongoing energy transition. Collaborating to push the boundaries of battery cell technology, the Center for Digitalized Battery Cell Manufacturing (ZDB) at the Fraunhofer Institute for Manufacturing Engineering and Automation IPA and acp systems AG have introduced a groundbreaking winding system for cylindrical battery cells. This innovative system offers flexible formats and designs, serving as a research and production platform to explore new cell formats, components, and tab designs. Moreover, it facilitates the development of large-format cells for future battery technologies, making it a pioneering advancement in the industry. The winding system, the first of its kind globally, is integrated into an automated, digitalized battery cell production infrastructure.

Electric vehicle batteries are composed of multiple modules, each containing numerous individual battery cells. These modules are essential components of batteries, contributing significantly to their value. The automotive industry has witnessed a growing preference for cylindrical battery cells, particularly in large cell formats. The collaboration between ZDB at Fraunhofer IPA and acp systems AG has resulted in the creation and implementation of a winding system for cylindrical battery cells, also known as round cells. This system functions as a versatile platform for research and production, enabling rapid testing of new cell formats, tab designs, and process optimization methods. The completion of this winding system marks a significant milestone in Europe's cylindrical battery cell manufacturing capabilities, catering to lithium-ion batteries and emerging technologies like sodium-ion batteries.

Julian Grimm, head of the research team at Fraunhofer IPA and Deputy Head of ZDB, emphasizes the importance of the winding process in battery cell production. He highlights the significance of the jelly roll, the core element of cylindrical cell production, and how the new winding system fills a crucial gap in the fully digitalized production chain. With the integration of the winding system, the production line achieves a comprehensive and seamless workflow, enhancing efficiency and quality throughout the manufacturing process.

The winding process involves several intricate steps to prepare a cell for use. During this process, the positive and negative electrodes, along with separators, are rolled together to form a jelly roll. Subsequently, the battery assembly requires precise positioning of the jelly roll, followed by the insertion of a rod electrode through the central hole for welding. Beyond its role in production, the winding system serves as a research platform for developing innovative cell systems, formats, and testing their quality, showcasing its versatility and adaptability in advancing battery technology.

One of the key features that sets the new winding system apart is its flexibility. This flexibility allows for the realization of various cell formats, sizes, and tab designs, including tabless designs that eliminate the need for welded tabs. Grimm explains that in large-format cells, the tab design plays a critical role in current collection and heat dissipation. By implementing individualized tab designs, such as tabless configurations, the system can enhance current conduction and heat dissipation, addressing challenges associated with larger cell formats. These innovative designs promote homogeneity in cylindrical cells, enabling the use of larger cells with increased active material to achieve higher energy density and extend the range of electric vehicles.