Material and production process optimization for lithium-ion batteries with ceramic solid state electrolytes
Motivation and procedure
The battery for automotive applications is the key component in the electrified powertrain. It has a direct influence on the acceptance hurdles of range, service life and safety and is largely responsible for the costs of an electric vehicle. Despite the immense and growing importance of battery cells for Germany as a business location, industrial battery cell factories have so far been located almost exclusively in Asia. Due to many years of experience of these countries in the mass production of battery cells, NPE does not recommend investing in the production of today's battery generations. The early development of know-how in the area of subsequent generations, which are technically superior to conventional lithium-ion batteries, is essential for a possible battery cell production in Germany.
The project investigates industrial processes for the production of battery cells with ceramic solid state electrolytes. The aim is to significantly increase the gravimetric energy density as well as the safety compared to conventional lithium-ion batteries. However, solid-state battery cells are still a long way from commercialization, mainly due to the lack of processes and materials tailored to them.
Research and development
- The lithium-ion conductivity of oxidic solid electrolytes is lower than that of conventional liquid electrolytes, which makes a thin-film design necessary. Suitable ceramic solid state electrolytes are therefore developed and produced. These are specially optimized for processing using thin-film technologies in order to reduce the internal resistance of the battery even in industrially manufactured cells.
- New manufacturing processes are being developed to overcome material incompatibilities during the indispensable high-temperature sintering step. Specifically, the focus is on two laser-based and one handling process.
- For mechanical stacking, electrical contacting and subsequent packaging of the battery, several layered composites consisting of mixed cathode/ceramic electrolyte/anode must be suitably handled in an inert atmosphere. In contrast to button cells usually found in laboratories, this is the only way to create battery cells that are relevant for industrial applications.
- Besides the development of suitable materials, the main focus is on scalable manufacturing processes. These will be optimized with respect to their production parameters in order to examine solid state battery technology with regard to its technical and economic competitiveness to conventional lithium ion batteries.
Research and project partners
- PEM of RWTH Aachen University
- Forschungszentrum Jülich GmbH, Institute for Energy and Climate Research, Materials Synthesis and Manufacturing Processes (IEK-1)
- Fraunhofer Institute for Laser Technology (ILT)
- German Aerospace Center (DLR) - Helmholtz Institute Ulm (HIU)
- University of Duisburg-Essen
- H.C. Starck Tantalum and Niobium GmbH
- LIMO Ltd.
- Aixtron SE
- Jonas & Redmann Automation Technology GmbH
Research funding in the 7th Energy Research Programme
Project duration: 01.01.2019 - 31.12.2021