In a recent publication in eTransportation, the Chair of Automotive Technology at TUM presents a novel methodology for impedance-based early detection of thermal runaway (TR) and precise temperature estimation in large-format lithium-ion batteries—both at the cell and system level. The study focuses on realistic battery modules with parallel-connected cells, as used in vehicles like the BMW iX3 (G08).
The proposed method minimizes interference effects at very low cell impedances (< 1 mΩ) and enables temperature estimation with an accuracy of less than 1 K in the range of –10 to 30 °C. Even under inhomogeneous temperature distributions, the method provides reliable trends and, with further extensions, enables early detection of TR events—making a significant contribution to the functional safety of automotive battery systems.
🔗 Read the study: https://doi.org/10.1016/j.etran.2025.100424