Executive Summary : | Safety concerns associated with the use of batteries in EVs under high current and elevated ambient temperatures remain an unaddressed research problem. A critical issue with high temperatures in lithium-ion cells is the risk of thermal runaway, which occurs when the temperature within the cell in any region increases beyond a critical value over which the exothermic decomposition of the cell materials gets initiated. Eventually, the stored internal thermal and electrochemical energy gets released violently in a catastrophic event. While researchers have been studying the thermal runaway events using expensive and time-consuming experiments, theoretical modelling of this phenomenon has received very little attention. The interplay and criticality of reactions are yet to be deciphered due to the short time span within which the cell goes from operationally functional to exothermic explosion. We propose to simulate these events by mimicking the dynamics of a lithium-ion cell using the concentrated solution and porous-electrode theories. The objective of this work is to mathematically simulate a thermal runaway event in lithium-ion batteries by coupling of the thermo-electrochemical effects with exothermic reaction kinetics. It is expected that this project will lead to a better understanding of thermal runaway and address the safety of lithium-ion batteries. |