Toxic Gas and Particle Emissions from Lithium-Ion Battery Fires

XIAOLIANG WANG, Matthew Claassen, Bjoern Bingham, Judith Chow, John Watson, Yan Wang, Desert Research Institute

     Abstract Number: 330
     Working Group: Combustion

Abstract
Lithium-ion batteries (LIB) are a ubiquitous component in modern consumer products. However, they pose a considerable safety risk due to their high energy density and toxic ingredients. Furthermore, the cells are at risk of thermal runaway, a process that can lead to rapid and violent combustion. LIB fires pose a catastrophic risk if they occur in enclosed spaces, where combustion emissions cannot be vented, or occupants cannot be evacuated. Such scenarios include LIB fires on spacecraft, aircraft, submersibles, mines, tunnels, or subway systems, where ventilation and evacuation are challenging. Moreover, inhalation of LIB fire smoke is also a health threat to firefighters. It is therefore necessary to properly characterize gas and particle emissions of LIB combustion to understand their health risks and determine the best methods for fire detection, suppression, and clean up.

This study characterized the gas and particle emissions from thermal runaway driven combustion of two LIB types (cylindrical lithium-iron-phosphate [LFP] cells and pouch-type lithium cobalt oxide [LCO] cells), each at five charge levels between 0% and 100%. Emissions from cell venting and flaming combustion were analyzed in real time and collected on filters for subsequent chemical analyses. A large amount of hydrogen fluoride (HF) was released during thermal runaway, sometimes exceeding the immediate danger to life and health (IDLH) concentration limit. Depending on charge level and combustion behavior, the PM2.5 composition was dominated by organic matter (OM), elemental carbon (EC), and/or phosphate. LFP cells had higher emission factors for HF and PM¬2.5 than LCO cells. For HF, the emission factors were 37–77 mg/Wh for LFP and 10–13 mg/Wh for LCO; while for PM2.5, the emission factors were 67–140 mg/Wh for LFP and 35–45 mg/Wh for LCO.