On 25 November 2021 Mathias Henriksen (USN) will hold a trial lecture and defence his thesis for the degree philosophiae doctor (PhD) in the doctoral program Program Process, Energy and Automation Engineering. The thesis is entitled “A study of premixed combustion of gas vented from failure LIBs”, and the dissertation can be followed both physically on campus Porsgrunn and digitally via Zoom.
Mathias’ PhD thesis can be found here
Have you ever wondered why Li-ion batteries cause fires and may even cause explosions? When Liion batteries fail, hot, reactive, and flammable gasses are vented, and fires and explosions can occur. In this Ph.D. study, the explosion capability of the gas vented from failed Li-ion batteries is the focus.
Li-ion batteries are today the leading electrical energy storage system due to high energy density, high specific energy, and low maintenance requirement compared to other traditional batteries. They are used in many products today, perhaps most commonly in electronic devices such as laptops, cell phones, and cameras. They are also an attractive option for large-scale energy storage, such as power grid systems and electric vehicles. However, the combination of flammable organic electrolytes and the release of oxygen at elevated temperatures in Li-ion batteries present a potential hazard. Various fires and explosions due to failing Li-ion batteries have been reported in the past.
This thesis presents results from two experimental setups, a 20-liter explosion sphere, and a 1-meter explosion channel. In the 20-liter explosion sphere, the explosion pressure, the rate of explosion pressure rise, and the laminar burning velocity (LBV) have been determined for various gas compositions vented from failed lithium-ion batteries. The results show that some of the gases vented have similar explosion characteristics as that of propane. In addition, the burning velocity for all gas compositions analyzed ranged from 0.3 m/s to 1.1 m/s, illustrating the influence of certain vented species and their concentrations.
The experimental results obtained from the 1-meter explosion channel were used to evaluate the prediction accuracy of a computational fluid dynamic (CFD) method for simulating an explosion from gases vented from failing LIBs using only open-source software. Three different gas compositions and three different channel geometries have been experimentally and numerically studied. Overall, the results show that the CFD method gave an acceptable model performance when comparing the experimental and numerical results.
The novelty of experimental and theoretical results contributes new and vital knowledge. The results are of practical importance in safety assessment and strongly needed as the new energy economy emerges.
The work was carried out at the University of South-Eastern Norway Campus Porsgrunn, Norway, part of the zero-emission program FME-MoZEES.