Experimental Investigation on Thermal Runaway Propagation in Lithium-Ion Battery Cell Stack

The propagation behavior of a prismatic state-of-the-art prototype lithium-ion battery (NMC811 - graphite) is examined in a 5 cell stack experiment in order to evaluate the influence of components that come along with the integration into a battery pack such as cooler, module structure or housing. A total number of 15 experiments are conducted (5 different setup variants with 3 test repetitions each). Thereby, the propagation time is evaluated and compared. The results show that for example the integration of the cell stack into a housing leads to a total propagation time that is 48.7% of the reference setup's propagation time without housing. This study helps not only to get a better understanding of the TR propagation process in general, but also to estimate the thermal runaway propagation behavior on module or pack level by conducting tests on a smaller scale with reduced costs.