The Influence of Different Cooling Concepts on Thermal Runaway Propagation

Battery thermal runaway is a serious safety concern while catering to high power requirements and faster charging abilities of electric vehicles (EVs). Two different battery cooling concepts, cold plate and immersion cooling are investigated to address the challenges of thermal runaway through numerical simulations. Thermal runaway is a complex 3D multi-physics problem that requires large computational efforts. Therefore, it is desired to have not only accurate but also a faster solution. A synergetic 1D-3D modelling approach is implemented to reduce the simulation time. Pseudo-two-dimensional (P2D) electrochemical battery models along with chemical kinetics model derived from Arrhenius equations are used and coupled to thermal and flow domain to predict three different phases of thermal runaway, namely, initiation, ignition, and propagation. The chemical kinetic reactions driving the thermal runaway with heat generations and venting gas phenomena are embedded into GT-AutoLion, a battery simulation tool of GT-SUITE. In certain extreme operating scenarios, thermal runaway triggered in one cell is seen to propagate to other cells in the case where the cooling was based on cold plate, whereas in case of immersion cooling the propagation of thermal runaway is contained. In summary, the presented simulation strategy found to be effective in choosing and designing the right cooling concept from the safety point of view.