Abstract Title   From Lithium Plating to Lithium – Ion Cell Thermal Runaway Abstract Author(s)   Celina J. Mikolajczak, John Harmon, Priya Gopalakrishnan, Ramesh Godithi, Ming Wu Abstract Presenter   Celina J Mikolajczak Abstract   Understanding the detailed mechanisms for cell internal short initiated thermal runaway in lithium ion cells is central to developing strategies to prevent these incidents: from assessing the potential safety of new cell materials to assessing quality of current production cells. Studies have been conducted to determine the areas of a cell that are most susceptible to initiating thermal runaway based upon the amount of power that can be produced by a short in that area. However, to date, these studies have been conducted assuming undamaged electrode materials. Our examinations of failed cells suggest that thermal runaway inducing internal short circuits can occur throughout cells, including locations where other studies indicate low susceptibility. Our examinations also suggest that cell internal faults may develop in regions of electrode degradation, particularly in areas of localized lithium plating. We consider the impact of both lithium dendrites and “dead lithium” fragments on initiating cell thermal runaway from a metal combustion perspective. We present a brief summary of literature regarding dispersed metal combustion and lithium metal burning, specifically with regards to the likelihood of ignition of dead lithium fragments, expected products of combustion, and the probable reaction temperatures and heat release from the reaction of dead lithium fragments. We present experimental data showing the effect of lithium plating on heat release within lithium ion cells, and propose a mechanism for cell thermal runaway development from areas of localized lithium plating. Finally, we explore the possibility of slow, relatively benign oxidation of dead lithium fragments, and conditions likely to enhance such oxidation.