Electric vehicles as we know are designed without traditional exhaust systems since they do not rely on internal combustion engines. However, Stellantis believes an exhaust system could still serve a crucial role in BEVs — but not for the reasons one might expect. There’s still the V8 Hellcat, for that.
Rather than simulating the sound of combustion engines, as some automakers have experimented with (Dodge and Abarth too, not with good results), Stellantis has developed a system aimed at improving safety by preventing or mitigating battery fires. This innovative concept has been detailed in a patent recently published by the United States Patent and Trademark Office (USPTO) in January 2025.
Addressing thermal runaway
At the heart of this patent is a focus on safety. When EV batteries fail due to short circuits, overcharging, or mechanical damage, they can undergo a phenomenon known as thermal runaway. This process can cause the affected battery cells to release flammable gases such as methane, ethane, ethylene, and acetylene. If not managed properly, these gases can escalate the situation into a full-blown fire, posing significant risks to both passengers and first responders.
Stellantis’ proposed exhaust system aims to channel these hazardous gases away from the battery pack, reducing the likelihood of ignition and limiting fire propagation. Rather than acting as a simple vent, this system would chemically treat the expelled gases to neutralize their flammability, much like how catalytic converters in traditional cars reduce harmful emissions. This unique approach positions Stellantis at the forefront of battery safety innovation in the EV space.
The concept, while intriguing, raises questions about its real-world application. Modern EV batteries are already equipped with advanced monitoring systems and sophisticated cooling mechanisms designed to minimize the risks of overheating and failure. While achieving absolute safety is impossible, today’s battery packs are engineered with multiple safeguards in place.
Nonetheless, automakers and researchers are continually seeking ways to enhance battery safety, and Stellantis’ exhaust system could represent another step forward in this pursuit. Whether this technology makes its way into production vehicles or remains a theoretical innovation remains to be seen. If implemented, it could significantly improve fire prevention measures in EVs, setting a new industry standard for battery safety.
