Project partners thyssenkrupp System Engineering GmbH, IAV GmbH, Daimler AG and the Fraunhofer Institute for Ceramic Technologies and Systems IKTS are developing bipolar Li-ion batteries and processes for their fabrication in the EMBATT-goes-FAB project sponsored by the German Federal Ministry for Economic Affairs and Energy.

With the EMBATT battery, the project partners are pursuing a new approach to achieving system-level energy densities of more than 450 Wh/l and hence making the range of electric vehicles suitable for everyday use.

These bipolar Li-ion batteries, like fuel cells, consist of stacked electrodes connected in series. In contrast to conventional Li-ion batteries, these electrodes are, as the name indicates, bipolar. This means that the active materials for the battery cathode and, overleaf, the active materials for the anode are applied to a common electrode carrier.

The individual Li-ion cells are then no longer packed separately in aluminum housings. Only the finished stack of electrodes is given a fixed housing. This eliminates housing components and connecting elements, which saves costs and space in the vehicle.

The freed-up space can be filled with more active material. As a result, the battery can store more energy and the vehicle can drive further. Li-ion bipolar batteries have so far only been investigated on a laboratory and pilot scale.

By researching scaled manufacturing technologies and integration solutions, the project aims to advance the industrialization of bipolar batteries.

The motivation for the four project partners to take this technology to the next level of maturity is obvious, as is the incentive for the Federal Ministry of Economic Affairs and Energy, which will provide financial support for the “EMBATT-goes-FAB” project over a period of two years.

The partners must be closely interlinked in order to master the new challenges. These range from the production of improved bipolar electrodes based on lithium-nickel-manganese-cobalt oxides and graphite as storage materials (Fraunhofer IKTS), to the scaling of assembly technology up to a size of 1000 x 30 cm² (thyssenkrupp System Engineering), the incorporation of an electric battery monitoring system (IAV GmbH), and safety simulations to address specific vehicle requirements (Daimler AG).