Are Electric Vehicle Battery Fires A Significant Concern?

Electric vehicles (EVs) are becoming increasingly popular as consumers seek more environmentally friendly transportation options. However, concerns about the safety of EVs, particularly regarding battery fires, often arise. In this blog, we will explore the reality of electric vehicle battery fires and whether they are really something to be concerned about.

The Risk of Electric Vehicle Battery Fires

Electric vehicle battery fires are rare occurrences. In fact, data suggests that the fire risk is significantly higher for petrol and diesel vehicles than for EVs. Although there have been recent reports of electric vehicle fires, the overall statistics show that these incidents are infrequent. To understand the risk of electric vehicle battery fires, it is important to compare them to traditional vehicle fires and analyse recent studies.

Comparing EV Fire Incidents to Conventional Vehicle Fires

According to EV FireSafe, an Australian firm tracking passenger electric vehicle battery fires worldwide, there have been only 474 verified electric vehicle battery fires from 2010 to 2024, out of an estimated 30 million electric vehicles on the road.

In comparison, traditional vehicles powered by internal combustion engines have a much higher fire risk. A report by the Swedish Civil Contingencies Agency found that internal combustion engine vehicles were 20 times more likely to catch fire than electric vehicles in Sweden. These statistics highlight that electric vehicle battery fires are relatively rare compared to fires in conventional vehicles.

The Rarity of Electric Vehicle Battery Fires

In Australia, there have been only four electric vehicle battery fires over the same period, with one linked to arson and the other three occurring in structures that burned down and destroyed the vehicles. These incidents suggest that the fires did not originate in the batteries themselves. It is important to note that the number of electric vehicles in Australia during these 14 years was relatively low compared to recent years.

What Causes Battery Fires in Electric Vehicles?

Many things can trigger electric vehicle battery fires and one common cause is thermal runaway. This occurs when an internal short circuit triggers a chain reaction in the battery pack, leading to excessive heat and combustion. 

Also, physical damage from collisions, manufacturing defects, battery faults, workshop repairs, arson, or external fires can contribute to battery fires in electric vehicles. Let’s understand the science behind EV battery combustion and the common factors that can lead to thermal runaway.

The Science Behind EV Battery Combustion

When an electric vehicle battery is damaged, an internal short circuit can trigger a chain reaction known as thermal runaway. This reaction causes the battery pack to generate more heat than it can dissipate, leading to a fire. 

About 95% of battery fires are known to be ignition fires, which produce jet-like directional flames, while the remaining 5% involve a vapour cloud explosion. 

Battery technology plays a crucial role in the likelihood and severity of thermal runaway. Different types of batteries, such as nickel-manganese-cobalt (NMC) and lithium-iron-phosphate (LFP), have different thermal characteristics and risks of combustion.

Common Factors Leading to Thermal Runaway

Several factors can contribute to thermal runaway in EV batteries. These include:

• Physical damage to the battery pack from collisions or accidents

• Exposure to direct sunlight, which can increase the temperature of the battery

• Hot surroundings or high ambient temperatures

• Manufacturing defects in the battery or battery management system

• Overcharging or improper charging practices

Safety Measures for EVs

To safeguard electric vehicles, a range of safety protocols and regulations are enforced. This includes utilising battery management systems (BMS) to oversee and regulate the battery's temperature, voltage, and current. Global standards for EV safety, such as those established by the Australian Building Codes Board, help guide the design, construction, and operation of electric vehicles. Emergency services also play a crucial role in responding to electric vehicle battery fires and ensuring the safety of occupants and the public.

Battery management systems (BMS) have evolved significantly to enhance the safety of electric vehicles. Advances in BMS technology have enabled better thermal management, early detection of issues, and improved safety features. EV FireSafe recommends that only qualified electricians handle the installation and maintenance of BMS systems to make sure safety standards are met. The ongoing research and development in BMS technology is constantly improving the safety and reliability of electric vehicle batteries.

Debunking The Myths Around Electric Vehicle Safety

Social media often perpetuates myths and misinformation about electric vehicle safety. Some common myths include exaggerated claims about the frequency and severity of electric vehicle battery fires or the toxicity of battery emissions. We can only debunk these myths by providing evidence-based information and stats that can help dispel misconceptions. It is important to rely on reliable sources and expert opinions when evaluating the safety of electric vehicles rather than solely relying on social media narratives.

How To Prevent EV Battery Fires

EV owners can adopt some of these strategies to help minimise the risk of electric vehicle battery fires by: 

• Regularly inspecting the battery pack for physical damage or signs of wear

• Following manufacturer-recommended charging practices and avoiding overcharging

• Participating in fire safety training to learn how to respond to battery fires

• Storing the vehicle in a cool and well-ventilated area, away from direct sunlight or extreme heat

As electric vehicle ownership continues to grow, owners should follow these best practices to minimise the risk of battery fires in their vehicles. One of the most crucial steps to follow is the manufacturer's recommended everyday charging limits and servicing requirements. EV owners should also avoid tampering with or removing the battery without the assistance of a qualified electrician. It is important to comply with any EV recalls issued by the manufacturer to address potential fire risk concerns. Additionally, EV owners should be aware of the operating temperature range of their vehicle's battery and avoid exposing it to extreme heat or direct sunlight for extended periods.

In response to the unique challenges posed by EV battery fires, there have been significant innovations in EV fire suppression technologies. These innovations aim to improve the safety of EVs and withstand battery fires. One innovation is the development of structural batteries, which embed battery cells within the chassis of the vehicle. This design helps contain fires and prevent them from spreading to other parts of the vehicle. Also, emergency services are adapting to the challenges of EV battery fires by utilising specialised equipment and techniques. For example, water drills and high-pressure water mist trays are being used to directly target and extinguish battery fires.

The Future of Electric Vehicle Safety 

The advancement of electric vehicle safety relies on continuous research in battery technology. Engineers are working on creating safer battery systems by exploring chemistries such as solid-state and sodium-ion batteries. The research aims to understand and prevent battery fires as electric vehicles become increasingly common. By understanding the root causes of battery incidents, using advanced management systems, and not spreading misinformation, the overall safety of electric vehicles on the roads can be improved.