Detailed characterization of particle emissions from battery fires

Abstract

Lithium-ion (Li-ion) batteries that are becoming ubiquitous in various applications may be susceptible to thermal runaway when subjected to certain abuse factors. Fire ensuing from such a thermal runaway event results in significant release of gaseous and particle emissions that pose a critical safety risk to human health. This program was focused on performing detailed characterization of particle emissions from Li-ion battery systems that experience thermal runaway. Four identical lithium iron phosphate (LFP) modules and one nickel manganese cobalt oxide (NMC) module were each subjected to thermal runaway. Two LFP modules and the NMC module were triggered into runaway via nail-penetration, while the remaining two LFP modules were triggered into runaway via over-charging. Particle emissions were characterized in terms of particulate matter mass (PM2.5), real-time total (solid + volatile) and solid PN/size (5.6–560 nm), real-time black carbon, organic/elemental carbon partitioning and volatile fraction of PM2.5. Gaseous emissions were measured using a real-time Fourier Transform Infrared spectrometer. Results suggest that battery fires can result in significant particle and gaseous emissions that may be a function of initiation mechanism, battery chemistry, and cell arrangement within a module among other variables. LFP modules subjected to nail penetration yielded relatively less emissions as propagation was not observed. Over-charging LFP modules resulted in significant emissions that showed a continuous increase till peak levels were reached followed by a gradual decrease. PM2.5 emissions ∼380 g/h and total PN emissions ∼1.5E + 17 particles/h (or 1.3E07 part./cm3) were observed. Nail-penetration of the NMC module resulted in several distinct peaks due to propagation of runaway from cell-to-cell. This module resulted in the highest emission rates of 551 g/h of PM2.5 and 2.1E + 17 particles/h (or 1.9E07 part./cm3) of total PN.Copyright © 2022 American Association for Aerosol Research