Insights on thermal runaway of Li-ion cells from The Battery Failure Databank

Understanding the risks associated with thermal runaway of Li-ion batteries is critical for designing safe cells and battery systems. The thermal response of cells can greatly vary for identical cell designs tested under identical conditions, the distribution of which is costly to fully characterize experimentally and cannot be captured by deterministic models. The Battery Failure Databank contains robust, high-quality data from hundreds of abuse tests spanning numerous commercial cell designs and abuse testing conditions. Data was gathered using a fractional thermal runaway calorimeter and contains the fractional breakdown of heat and mass from ejected and non-ejected cell contents, as well as high-speed radiography of the internal structural response of cells during thermal runaway. This presentation will provide an overview of insights in the thermal and mass ejection behaviours of commercial cells during thermal runaway.

Donal Finegan is a staff scientist at the NREL Center for Integrated Mobility Systems. His work focuses on understanding degradation and failure mechanisms of Li-ion batteries and taking steps to improve the performance and safety of cells and battery systems. His research has spanned numerous conventional and next generation energy-storage materials. He is a frequent user of international synchrotron facilities and has pioneered the application of high-speed X-ray imaging for diagnosing battery failure mechanisms during thermal runaway. Finegan manages NREL’s X-ray computed tomography (CT) laboratory and is part of several DOE battery research programs where his focus is on characterization. He actively engages with industry, research institutions and universities. He is a visiting lecturer at University College London (UCL), has published over 80 journal articles, and his work has received several internationally recognized awards.