Within the VLAIO living lab project CaDaNS, KU Leuven, Bikebat and Sortbat are exploring how
to reuse discarded e-bike batteries more efficiently. One option is to remove and reuse
individual cells from packs that can no longer be repaired. A key challenge in this process is
testing the condition of each cell.
Today, these cells first undergo a simple resistance test, after which passed cells are cycled (charged and discharged) to measure their capacity and determine their state of health (SoH). This takes several hours per cell and requires costly hardware. In our recent conference paper presented at CIRP LCE 2025, we propose to perform a short two minute Electrochemical Impedance Spectroscopy (EIS) test at the outset instead of only measuring internal resistance. We demonstrate that this test is a good indication of remaining capacity, allowing cycling hardware to be used more efficiently. In addition, the acquired SoH information can be linked to the Digital Product Passport (DPP) of the new battery pack in which the cell is reused, providing valuable information to indicate how long second-life batteries are expected to last. The next step for the KU Leuven team is to develop supporting tools to collect and exchange this DPP data efficiently.
Reference:
Sterkens, W., Peeters, J. (2025). Predicting the Capacity Fade of Discarded Batteries with Electrochemical Impedance Spectroscopy. 32nd CIRP Conference on Life Cycle Engineering, Manchester. https://doi.org/10.1016/j.procir.2024.12.116
Acknowledgements:
This work was supported by the VLAIO living lab project CaDaNS (“Circulair Datagedreven Waardenetwerk rondom S-pedelecs”)
