A calorimetry technique is developed to measure the energetics of an 18650 Li-ion battery in thermal runaway. The technique uses the battery as a calorimeter with temperature and mass loss measurements to analyze the energetics. Runaway is induced by heating of the battery. Only one battery is investigated over a range of heating power and state of charge (SOC). The dynamics of the battery are investigated including time events, temperature, mass lost and energies. The total energy in runaway is manifested by the internal energy stored in the battery and the enthalpy of the ejected mass. Combustion of the ejected gases is not studied here. Here a safety vent first causes the release of gases, then this is followed by the more dominant ejection during runaway. Vent times decrease dramatically with heating power. The duration of runaway decreases with the SOC, and runaway energy increases with the SOC. The total energy measured in runaway is compared to an alternative technical to show its accuracy. The need to assume a specific heat of the ejected mass in the current technique has an effect on accuracy. Also the possibility of melting in runaway is not included in the current technique.

International Seminar on Fire and Explosion Hazards (9; 2019; Saint Petersburg, Russia). Proceedings of the Ninth International Seminar on Fire and Explosion Hazards [Электронный ресурс]: 21-26 April 2019, Saint Petersburg, Russia. Vol. 2 / Peter the Great St. Petersburg Polytechnic University, Autonomous Non-Profit Organization "Fire and Explosion Safety", Gefest Holding Ltd ; [edited by A. Snegirev [et al.]. — Электрон. текстовые дан. (1 файл : 98,7 Мб). — Saint Petersburg, 2019. — Загл. с титул. экрана. — Свободный доступ из сети Интернет (чтение, печать, копирование). — Adobe Acrobat Reader 7.0. — <URL:http://elib.spbstu.ru/dl/2/k19-97.pdf>. — <URL:http://doi.org/10.18720/SPBPU/2/k19-97>.