Fraunhofer Institute for Industrial Mathematics ITWMEfficient battery technologies are crucial for achieving national and European climate targets. Although lithium-ion systems currently dominate the market, they are increasingly reaching their physical and technological limits. Lithium metal batteries are therefore considered promising successors with great potential. In the EU project »STELLAR«, we are working with 16 European partners to develop a cost-efficient roll-to-roll test facility for the production of lithium metal anode foils.
Project manager at Fraunhofer ITWM Stefan Duran presents the contents of the STELLAR project.
© Fraunhofer ITWM
Efficient Manufacturing and Precise Monitoring of Lithium Metal Anodes: Progress Through Roll-To-Roll Technology
Project »STELLAR«: Measurement Technology for the Next Generation of Lithium Metal Batteries
The foil runs continuously through a system, is coated with a precise layer of lithium, and then rewound. This technology enables an industrial production capacity of around 60 kilometers of anode foil per year. The thickness of the lithium layer can be precisely controlled between 5 and 15 micrometers. In this way, we are laying the foundation for a safe and sustainable generation of batteries.
Lithium Metal Batteries – The Key to the Next Generation of Storage Technology
Compared to conventional lithium-ion systems, lithium metal batteries offer significantly higher energy density: they store more energy for the same weight, enabling longer operating times – a clear advantage for electric mobility and portable electronics.
The biggest challenge lies in the safe and reproducible production of the sensitive anodes, as lithium is highly reactive. For this reason, the very thin lithium layer is applied to wafer-thin copper foils in specially controlled vacuum chambers.
Inline Quality Control Under Vacuum Conditions
A key focus of our work in project »STELLAR« is on inline monitoring of film properties throughout the entire production process, especially under the demanding vacuum conditions in which lithium metal anodes are produced. Only precise and continuous quality monitoring can guarantee batteries that are durable, resource-efficient, and suitable for modern applications.
We contribute our comprehensive expertise in optical measurement technology to this project. We are investigating various methods for the inline monitoring of key parameters such as layer thickness, surface roughness, electrical conductivity, and cut edge quality in terms of their practical applicability and performance. With our broad portfolio of measurement technology, we tailor the most suitable methods to the very specific requirements of each individual application.
Process for manufacturing lithium metal anode foils
Project Funding and Duration
The project is being coordinated by the Belgian company Avesta Holding, a developer and manufacturer of lithium batteries, where the pilot plant is demonstrated. The European Commission is providing a total of €7.9 million in funding for the four-year project period from June 1, 2025, to May 31, 2029. We receive approximately €757,000 in funding for the development of optical measurement technology.
Project Partner
- AVESTA Holding
- AGC Glass Europe
- Fundación CIDETEC
- Comau S.p.A
- Asociación Centro Tecnológico CEIT
- Fraunhofer-Gesellschaft
- Carl Zeiss AG
- Carl Zeiss Spectroscopy GmbH
- Università di Torino (Universität Turin)
- Politecnico di Milano
- IKERLAN, S. Coop.
- HSSMI Consulting Ltd
- LiPlanet e.V.
- INOVA+, Innovation Services S.A.
- CSEM, Centre Suisse d'Innovation de Renommée Internationale
- Belenos Clean Power Holding AG