In the current Energy transition context, the lithium battery is an essential technology to address the strong challenge of the electrical energy storage. However, Li battery severe solicitations/loadings can lead to a thermal runaway phenomenon, which can cause an outbreak of fire, even an explosive combustion of the cell or of the whole battery pack. If this phenomenon is well known, the research and development dedicated to the battery safety is emerging and must be consolidated. The post-doctorate global objective is to develop a numerical modelling and simulation strategy for thermal runaway occurring when a Li battery is subjected to mechanical/thermal/electrical abuse, in order to gain an understanding of the phenomenon, estimate the thermal spreading risk as a result of gas combustion, or study the runaway mechanical consequences (fluid structure interaction). This strategy relies on physical testing campaigns carried out as part of the post-doctorate, and on numerical tools developed by CEA (EUROPLEXUS, Cast3M). The work will be organised into three main content areas: Understanding and modelling of the phenomena on the basis of experimental tests (shock tube, abusive tests), Development of a numerical model representative of identified phenomena, Modelling including fluid-structure interaction (case deformation due to pressure increase).