UL Research Institutes 1 article published in JoVE Engineering In Situ Gas Analysis and Fire Characterization of Lithium-Ion Cells During Thermal Runaway Using an Environmental Chamber Byoungchul Kwon1, Wohan Cui1, Ankit Sharma1, Ya-Ting Liao1, Fumiaki Takahashi1, Daniel Juarez-Robles2, Mohammad Parhizi2, Judith Jeevarajan2 1Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 2UL Research Institutes Here, we describe a test procedure developed to characterize thermal runaway and fires in lithium-ion cells through in situ measurements of various parameters in an environmental chamber.