Fire Blankets Are Not Enough For EV Fire Hazards – Korean Study Finds

As electric cars become more popular, concerns around safety, particularly during emergencies like fires, have drawn significant attention. A recent Korean study highlights that using a fire blanket alone may not be sufficient to control the unique fire hazards associated with electric vehicle (EV) batteries. Let’s explore the findings of this study and why it’s essential to rethink current firefighting strategies for EVs.

The Unique Challenge of EV Fires

Unlike conventional petrol or diesel cars (internal combustion engine vehicles), EVs are powered by large battery packs, often made of lithium-ion cells. These batteries store substantial amounts of energy, and when they fail, they can catch fire in a phenomenon known as thermal runaway. Once this process starts, it can be difficult to control due to the intense heat and potential for re-ignition, even after the initial fire is extinguished.

The Korean study revealed that standard fire blankets, commonly used to suffocate fires by cutting off oxygen, may not be sufficient to handle these fires. The study tested various methods and concluded that while fire blankets could contain visible flames, they could not prevent the spread of thermal runaway in the battery. This makes them ineffective as the sole firefighting solution for EVs.

Comparing Temperature and Smoke Emissions

Temperature
EV fires tend to reach significantly higher temperatures compared to fires in petrol or diesel cars. When an EV battery undergoes thermal runaway, it can reach temperatures exceeding 1,200 degrees Celsius (2,192 degrees Fahrenheit). This extreme heat can lead to rapid combustion and severe structural damage to the vehicle. In contrast, fires from ICE vehicles typically burn at lower temperatures, around 600 to 800 degrees Celsius (1,112 to 1,472 degrees Fahrenheit). The higher temperatures in EV fires can also cause surrounding materials to ignite more readily, complicating the firefighting process.

Smoke Emissions
The smoke produced during EV fires can also differ significantly from that of ICE vehicles. The combustion of lithium-ion batteries generates toxic gases, including hydrogen fluoride and other hazardous compounds, which can pose health risks to firefighters and nearby individuals. Additionally, the smoke from EV fires can be denser and more toxic than that from petrol or diesel fires due to the materials used in the batteries and vehicle components. In comparison, while ICE vehicle fires also produce harmful smoke, the chemical composition is generally less hazardous than that generated by burning lithium-ion batteries.

What is a Fire Blanket?

A fire blanket is a safety device designed to extinguish small fires. Made from fire-resistant materials, it works by smothering the fire, depriving it of the oxygen needed to burn. Fire blankets are commonly used in homes, labs, and industrial settings and are especially effective for tackling kitchen or electrical fires.

In the context of EV fires, fire blankets are deployed over the vehicle to contain the fire. While this method is helpful for some aspects of fire control, the Korean study shows that EV battery fires behave differently from traditional combustion-based fires, making a fire blanket less effective than expected.

Commercial Fire Blankets for EV Fire Safety

In the evolving landscape of electric vehicle (EV) safety, several commercial fire blankets have emerged, claiming to withstand extreme temperatures during fire incidents. For instance, the Bridgehill EV-rated fire blanket is crafted from pyroxene with a polymer silicone coating, offering remarkable short-term heat resistance of up to ±2500 °C (4532 °F) and long-term resistance of ±1500 °C (2732 °F).

These specifications are designed to address the unique challenges posed by EV fires, providing enhanced protection for emergency responders and vehicle owners alike. As the demand for EVs continues to grow, investing in these specialized fire safety solutions becomes increasingly essential to ensure safe handling in the event of fire emergencies.

Korean Study: Key Findings

1. Limited Impact on Battery Fire Progression: Fire blankets could smother surface flames but were not effective in stopping the internal spread of thermal runaway in the EV battery. The heat generated continued to propagate within the battery cells, increasing the risk of re-ignition.
2. Challenges with Re-ignition: One of the biggest dangers of EV fires is the risk of re-ignition. Even when a fire is successfully suppressed, EV batteries may reignite due to the ongoing thermal reactions in the cells. Fire blankets do not offer long-term suppression for these fires, leaving room for potential danger.
3. Additional Cooling Required: The study emphasized the importance of water-based cooling systems alongside fire blankets. While the blanket can contain flames, it cannot lower the internal temperature of the battery. Without proper cooling, the risk of a secondary fire remains high.

A Comprehensive Approach to EV Fire Safety

The findings underscore the need for a more comprehensive firefighting strategy for EVs. Simply relying on fire blankets is insufficient. Instead, combining methods like:

• Fire Blankets: Useful for initial fire control and containing surface-level flames.
• Water Cooling Systems: Necessary to bring down the internal temperature of the battery and stop thermal runaway.
• Firefighting Foam and Extinguishers: Can be effective in specific cases, but their role in EV fire management should be part of an integrated approach.

Rethinking Emergency Response for Electric Vehicles

As the number of electric cars on the road continues to grow, it’s essential for emergency services, manufacturers, and vehicle owners to be well-prepared with the appropriate tools and knowledge to handle the specific fire hazards associated with electric vehicles (EVs). This study emphasizes the need for innovation in firefighting equipment for EVs, advocating for advanced methods that extend beyond traditional tools like fire blankets.

Electric vehicles are increasingly recognized for their safety features, and fires in EVs are exceptionally rare.

In fact, research indicates that electric cars, now exceeding 40 million worldwide, are considered by EV Firesafe to be 20 to 80 times less likely to catch fire than internal combustion engine (ICE) vehicles.

This statistic is reassuring for current and potential EV owners, as it underscores the advancements in battery technology, fire-resistant materials, and vehicle design that enhance overall safety.

While concerns about fire hazards are valid, it’s important to note that EV fires are often linked to specific conditions, such as manufacturing defects or severe accidents, rather than inherent risks associated with electric vehicles themselves. Moreover, the industry is continuously evolving, with manufacturers implementing stringent safety protocols and emergency response training for first responders. This proactive approach not only improves the overall safety of electric cars but also helps build public confidence in their use.

By fostering a better understanding of EV fire safety and equipping emergency responders with the right tools, we can ensure that the growing presence of electric vehicles on our roads is met with appropriate preparedness and knowledge.