Thermal and Electrochemical Analysis of Thermal Runaway Propagation of Samsung Cylindrical Cells in Lithium-ion Battery Modules

Thermal runaway propagation analysis at the module and cell level was performed using the Samsung 30Q 18650 cylindrical cells. Measurements such as cell enthalpy, maximum thermal runaway temperature, and thermal runaway onset and initiation temperatures were collected and shown to be consistent by means of accelerated rate calorimetry (ARC). This study showed, using the module billet as a thermal runaway propagation mitigation strategy, the cell energy was successfully absorbed during a failure event and prevented thermal runaway propagation from between cells. However, the module level tests showed average maximum temperatures that were 229 °C higher than the average maximum temperatures in the cell level tests, showing the importance of evaluating both the cell level thermal runaway response and the module level response, as they can be different. This work shows the differences between cell TR and module level TR and an effective mitigation strategy based on effective spacing and thermal mass.