Electric vehicles (EVs) introduce distinct challenges in fire safety, primarily due to their lithium-ion battery systems. While these batteries are both efficient and powerful, they can pose significant risks in the event of a fire. Traditional firefighting techniques rely on disrupting one of the elements of the fire triangle to successfully extinguish a fire. However, when dealing with a lithium-ion battery (LIB) fire, these methods can exacerbate the situation. After extinguishing an LIB fire, the battery may remain in a state of thermal runaway, releasing vapors that have the potential to be explosive. This critical factor must be carefully considered when managing an electric vehicle fire. Utilizing the appropriate equipment and adopting a strategic approach are essential to ensuring both safety and effectiveness. Below is a comprehensive guide to the best practices for handling an EV fire incident.

1. Early Detection and Prevention

Off-Gassing Recognition:

• Early detection is critical. If an EV starts to emit a chemical odor, hissing, or visible smoke, it may be off-gassing, indicating a potential thermal runaway. Recognizing these early warning signs and acting quickly can prevent a fire from fully developing. The gasses given off can be explosive in nature and consideration of this should be noted for the protection of people and property.

Preventive Measures:

• Battery Management Systems (BMS): Ensure the vehicle’s BMS is functioning correctly. A good BMS monitors battery health and can alert the driver to any issues that might lead to a fire.
• Regular Maintenance: Routine inspections of the battery system and associated components can identify and rectify potential hazards before they escalate.

2. Immediate Actions During an incident

Ensure Personal Safety:

• Evacuate the Area: If a fire starts or the vehicle is off-gassing, the first step is to ensure that all occupants are safely evacuated from the vehicle and that bystanders maintain a safe distance.
• Alert Authorities: Call emergency services immediately. Provide them with details about the situation, including that it involves an electric vehicle, as this information will dictate their response strategy.

Initial Containment (if safe):

• Vehicle Fire Blanket: If the fire has not yet fully developed and it is safe to approach, trained personnel may use a vehicle fire blanket to smother the flames and contain the fire. This can prevent the fire from spreading and buying time until emergency responders arrive.

3. Fire Suppression Strategies

Use of Water:

• Cooling the Battery: The most effective method to suppress an EV fire is to use large amounts of water. This helps cool the battery and stop the thermal runaway process. However, this requires substantial water volume and may not be immediately practical for all emergency situations.
• Continuous Application: Since EV batteries can reignite, it’s crucial to continue applying water until the battery has fully cooled. This might take hours, and the vehicle will need to be monitored even after the fire appears to be out.

Specialized Extinguishing Agents:

• FX Fluid: These are designed for fires involving flammable materials, which are part of the battery chemistry in EVs. While not always necessary, they can be useful in smll fire situations.
• Fire Blanket: These can help hold off ignition in the event of an off-gassing event or suppress flames and stop the spread of fire to other vehicles or nearby structures, they are generally less effective for the cooling required to stop thermal runaway in a lithium-ion battery. 
• Under Body Spray: As the battery compartment is on the underneath of a vehicle, cooling is the only way to get the thermal runaway temperature down sufficient enough where either runaway ceases or enabling time to move the car to a safer location.
• Consider PPV: As the gasses given off from and EV battery can be explosive, the incident commander should consider the use of PPV to disipate the explosive gasses.

4. Handling Re-Ignition Risks

Monitoring After Initial Extinguishment:

• Re-Ignition Potential: Due to the nature of lithium-ion batteries, there is a significant risk of re-ignition even after the fire is seemingly extinguished. Monitoring the vehicle for several hours after the fire is critical.
• Thermal Imaging: Firefighters often use thermal imaging cameras to monitor the battery’s temperature. This helps identify any hotspots that could indicate a potential re-ignition.

Transportation and Storage Post-Fire:

• Safe Quarantine: Once the fire is out, the vehicle should be moved to a designated safe area, away from structures, where it can be monitored for any signs of re-ignition.
• Specialized Containers: Some facilities may use containers designed to isolate a damaged EV battery, providing a controlled environment to manage any further risks.

5. Coordination with Emergency Services

Emergency Responder Preparedness:

• Training and Equipment: Fire departments and emergency services need specialized training to handle EV fires. This includes understanding the unique challenges posed by lithium-ion batteries and having the right equipment, such as thermal cameras and large water supplies.
• Communication: Clear communication with emergency responders is essential. Provide details about the EV’s condition, any observed off-gassing, and actions already taken (like the use of a fire blanket).

Pre-Incident Planning:

• Local Fire Departments: Work with local fire departments to ensure they are familiar with EVs and the specific risks they pose. Pre-incident planning can help them respond more effectively.
• Company Protocols: For companies operating EV fleets, it’s essential to have protocols in place for managing EV fires, including staff training, access to the right fire suppression tools, and coordination plans with emergency services.

6. Post-Incident Review and Learning

Incident Analysis:

• Reviewing the Event: After an EV incident, conduct a thorough review to understand what happened, how it was handled, and what can be improved. This analysis should involve all stakeholders, including the vehicle owner, fire services, and any other parties involved.
• Updating Protocols: Use the findings from the review to update safety protocols, training programs, and emergency response plans to better handle future incidents.

Advancing Safety Measures:

• Industry Collaboration: Engage with industry groups and other stakeholders to share knowledge and improve overall safety standards for EVs.
• Research and Development: Support and keep abreast of advancements in battery technology, fire suppression techniques, and vehicle safety systems that can reduce the risks associated with EV fires.

Conclusion

Dealing with an electric vehicle fire requires a specialized approach due to the unique characteristics of lithium-ion batteries. Ensuring safety involves a combination of early detection, proper suppression techniques, effective coordination with emergency services, and ongoing vigilance to prevent re-ignition. As electric vehicles become more common, continued education, training, and the development of new technologies will be essential to enhance safety and minimize the risks associated with EV fires.