Batteries are central to the technological advancement and operational efficiency of numerous modern applications ranging from portable electronic devices to electric vehicles and energy storage systems. In the realm of battery technology, ensuring the safety and efficiency of battery modules is crucial, particularly in high-performance applications where the risk of thermal runaway remains a significant concern. The increasing dependency on batteries demands enhanced focus on safety measures, particularly concerning thermal management to prevent incidents of thermal runaway. This presentation will examine how active cooling affects the behavior of battery cells during thermal runaway, specifically addressing the delayed onset of thermal runaway, the reduced severity of temperature increases, and the changes in cell dynamics as they approach critical conditions, which can mitigate gas release and provide additional time for safety interventions.

The experimental phase involved testing of battery modules equipped with an active cooling system. The tests were designed to imitate conditions that could lead to thermal runaway, thereby allowing the evaluation of the effectiveness of the cooling system under controlled extreme conditions. By methodically increasing thermal stress, the experiments aimed to pinpoint the operational limits of the cooling system and its capability to maintain cell temperatures within safe thresholds.

To conduct Thermal runaway and propagation tests, Fraunhofer ISE developed an advanced test bench with a volume of 500 liters and a unique spherical shape. To facilitate these tests, a new flange capable of integrating cooling pipes was developed, along with a customized sample holder to secure the cell module in place. The colling pipes are designed to remain attached to the module even under the impact of thermal runaway and propagation. These enhancements to the test bench created a controlled environment to accurately assess the influence of active cooling on the behavior of battery cells close to critical conditions. The focus was on observing changes and delays in the process flow due to the cooling system.

In conclusion, this presentation will analyze the impact of active cooling on specific thermal and chemical behaviors in battery cells under stress conditions, such as heat generation rates, temperature regulation, and cell-to-cell thermal propagation. Quantitative shifts in these parameters are examined to clarify the role of active cooling in altering thermal runaway dynamics and slowing propagation events. These insights are expected to contribute to refining thermal management models and guiding the development of more resilient safety protocols in advanced battery systems.