https://doi.org/10.1016/j.jhazmat.2026.143912
Abstract
This study assessed the physical, chemical, and toxicological properties of particulate emissions produced from lithium-ion battery fires. Commercially-available nickel manganese cobalt (NMC) battery modules were overcharged to trigger thermal runaway. The first experiment allowed the battery modules to burn without engaging any suppression system, while two additional experiments were performed with water and a potassium-based aerosol to suppress the battery fires. Results showed the formation of large diameter particles with geometric mean diameters of ∼360 nm, with their majority be below 1 μm. Depending on the experimental conditions, particle morphology revealed the generation of more spherical complex particles, while particle composition showed a mix of organic and inorganic agglomerates. Particle metallic composition was dominated by Li, Ni, Mn, Co, O, and Al, consistent with the chemistry of the battery modules. Medium and high molecular weight polycyclic aromatic hydrocarbons (PAHs) showed higher concentrations than lighter PAHs. Small-chain perfluoroalkyl and polyfluoroalkyl substances (PFAS) dominated the particle emissions, with the presence of legacy PFAS suggesting that these compounds are still used in the manufacturing of lithium-ion batteries. All particle samples induced elevated oxidative stress and inflammatory responses, and correlation analysis identified relationships between particle composition and toxicological outcomes.
Quotes:
Lithium-ion batteries power various consumer products used by millions of people across the world, including laptops and smartphones, personal electronic devices, and electric vehicles....Studies have shown that battery fires are responsible for the elevated emissions of hydrogen fluoride (HF) [6], [7]. HF is a well-known toxic compound to humans, which can be inhaled via the respiratory system or through dermal exposure causing corrosive and serious systemic toxic effects [8]. The HF formation is primarily originating from the electrolyte containing lithium hexafluorophosphate (LiPF6) and various types of lithium salts at high temperature conditions or from other sources containing fluorine, such as flame retardants present in the flammable electrolyte [7], [9]. Larsson et al. [10] studied the influence of different states of charge (SOC) in commercial lithium-ion batteries on HF emissions and found higher HF emissions for lower SOC values. Lecocq et al. [11] performed fire tests on a battery electric vehicle (BEV) and a conventional internal combustion engine vehicle, where they reported significant HF emissions from both vehicle technologies, but higher HF concentrations for the BEV as a consequence of the thermal runaway in a lithium-ion battery pack.