A second life for electric vehicle batteries

The project is part of the Flagship Initiative of Innosuisse, the Swiss Innovation Agency. The closing conference CircuBAT2025 takes place on 13 and 14 November in the BERNEXPO Foyer and will address the subject through the lens of science, politics and society.

Electric vehicles are key to making mobility more environmentally friendly. In particular, their core, the lithium-ion battery, offers significant potential to further improve their ecological footprint over the entire life cycle. This is where CircuBAT comes in. The creation of a circular economy model for automotive lithium-ion batteries was successfully implemented over a period of four years. “We have developed innovative solutions that are attracting worldwide attention. These solutions represent a first step on the way to closing the battery loop with stations distributed around the globe,” says project manager Andrea Vezzini of Bern University of Applied Sciences BFH.

Collaboration between research and the economy

BFH is the Leading House in the CircuBAT project. On the science side, six other Swiss research institutions are involved in the project: Empa, the Swiss Center for Electronics and Microtechnology (CSEM), the University of St. Gallen (HSG), the Eastern Switzerland University of Applied Sciences (OST), the Switzerland Innovation Park Biel/Bienne (SIPBB) and EPFL (Swiss Federal Institute of Technology) in Lausanne. These institutions are joined by 24 companies from the economy and industry, ranging from material specialists and manufacturing companies to users and providers of electric vehicles. The collaboration between science and the economy ensured that the project covered all phases of a battery’s life cycle and that the solutions developed could be tested in practice. Several of these solutions are about to be launched on the market or are being pursued in follow-up projects and start-ups.

Optimisation in all areas

The CircuBAT project focuses on identifying solutions that enhance sustainability in all phases of a lithium-ion battery’s life cycle. This includes extending the lifespan of batteries during their first use. This is achieved with the implementation of an interactive ‘Battery Expert System’, which allows a comparison in an intuitive form of the ageing process of a large number of batteries, and with new concepts for battery construction that make repairs easy. In addition, the project aims to put batteries to use as stationary energy storage systems after they have retired from their first mobility-related use.

In the course of the project, optimisation strategies for the safe and efficient operation of several battery packs with uneven degradation were implemented in a control system. Finally, the researchers developed automated solutions for demanufacturing sub-steps and new processes for direct material recovery. This aims to facilitate the incorporation of secondary raw materials into the production of new batteries and other applications. In addition to these technical aspects, the project also developed the Swiss circular economy model for lithium-ion batteries, which will enable future volumes to be estimated, for example for the Swiss second-life battery market. CircuBAT will therefore play a key role in decarbonising mobility in Switzerland and promoting the use of renewable energy.