Electrical Discharge Interaction with Lithium-Ion Battery Vent Gases: Investigations using High-Speed Imaging and Breakdown Analysis

Sammanfattning: The increasing drive for sustainable and eco-friendly transportation has made the electrification of cars a top priority in the energy and transportation sectors. Ensuring the safety of electrical vehicle (EV) batteries is of the utmost importance. This collaborative research project, conducted in partnership with Volvo Cars, focuses on optimizing battery safety by investigating the risks associated with battery fires. This study focuses primarily on lithium-ion batteries and explores the possibility of electrical discharge within them, as well as ignition behaviors resulting from thermal runaway. By examining the combination of electrical discharge and combustible gases, the project delves into the uncertainties surrounding electrical discharge as an ignition source in abused batteries to gain insights into associated risks and possible preventative design. Through the use of high-speed imaging and laser diagnostics, two experiments were performed to assess this interaction. With one experiment focusing on electrical discharge through different gas media, and the other focusing on the behavior of the combustion of ignited vent gases, many significant aspects are investigated and analyzed. The outcomes of this study provide valuable insight for enhancing battery safety, and create a stepping stone into this relatively unstudied field.