Warning: Don't let your beloved car catch fire

On January 18, 2025, the website of the Ministry of Public Security released figures showing that the number of motor vehicles in China reached 453 million, including 353 million automobiles and 31.4 million new energy vehicles. At the end of 2024, China’s population stood at 1,408.28 million, meaning that on average, one in every four people owns a car. In the course of vehicle use, therefore, a fire, once it occurs, often results in severe economic losses or casualties.

According to statistics from the fire department, the peak period for vehicle spontaneous combustion occurs from May to October each year. Among these incidents, passenger car fires account for the majority, comprising over 40%; fires occurring while the vehicle is in motion make up the majority, at around 70%; and electrical short circuits are the leading cause, accounting for over 60%.

I. How Many Types of Vehicle Fire Accidents Are There?

1. Two-wheeled, three-wheeled and four-wheeled electric vehicles

(1) On April 16, 2025, the Henan Fire Department's official WeChat account reported that an electric four-wheeled vehicle at a residential home in Xiayi County, Shangqiu City suddenly caught fire. Upon receiving the alarm, rescue personnel immediately rushed to the scene to handle the situation.

(2) At around 14:00 on May 25, 2025, the Nanchang Fire Department's official WeChat account released a report that a low-speed electric vehicle fire occurred under the Hongteng Elevated Road in Qingyunpu District, Nanchang City. The electric vehicle was in motion when it caught fire, and no casualties were caused. The direct economic loss from the fire was approximately 1,100 yuan. According to the fire investigation, the cause of the fire was an electrical fault short circuit. The electric vehicle brand was Yadea, the battery was the original battery, and the purchase time was within 3 years.

(3) On June 3, 2025, the Guizhou Fire public account released a report stating that in May, a total of 6 electric bicycle fires occurred across the province. By type of electric bicycle, there were 3 two-wheeled electric bicycles, 1 three-wheeled electric bicycle, and 2 four-wheeled electric bicycles.

2. Fuel vehicle fire accidents

CCTV News reported that in 2024, the fire incident rate for new energy vehicles dropped from 1.85 per 10,000 in 2021 to 0.96 per 10,000 in 2023, while the fire rate for fuel vehicles remained at around 1.5 per 10,000. Additionally, according to statistics from the National Fire and Rescue Administration, there were 18,360 spontaneous combustion accidents involving fuel vehicles in the first quarter of 2023. Based on the fuel vehicle ownership of 317.71 million at that time, the fire rate was 0.58 per 10,000.

2. Combustion and Spontaneous Combustion

1. Combustion is an exothermic, luminescent chemical reaction, typically accompanied by flames, light emission, and smoke. Combustion requires three essential conditions: a combustible substance, an oxidizing agent (oxidizer), and an ignition source (energy), commonly referred to as the “three elements of combustion.” Based on the conditions of its formation and the characteristics of its instantaneous occurrence, combustion is generally classified into four types: ignition, spontaneous combustion, flash combustion, and explosion.

2. Spontaneous combustion refers to the phenomenon in which, without the direct action of an external ignition source such as a spark or flame, a combustible material generates heat due to exposure to heat or through its own internal reactions, and this heat accumulates, causing the temperature to rise continuously until the material ignites on its own.

Spontaneous combustion can be classified into two forms: chemical spontaneous combustion and thermal spontaneous combustion. ① Chemical spontaneous combustion. This type of ignition phenomenon typically does not require external heating; instead, it occurs at ambient temperature through the substance's own chemical reactions, and is therefore conventionally referred to as chemical spontaneous combustion. Examples include matches igniting due to friction, explosives detonating upon impact, sodium metal spontaneously combusting in air, and coal spontaneously combusting due to excessive accumulation. ② Thermal spontaneous combustion. If a mixture of combustible material and oxidizer is uniformly heated in advance, as the temperature rises, the mixture will spontaneously ignite when heated to a certain temperature. This mode of ignition is conventionally referred to as thermal spontaneous combustion.

3. Classification of causes of vehicle fires

1. Electrical system: Fires caused by electrical faults such as short circuits, overcurrent, or poor connections in the vehicle's electrical wiring or electrical equipment.

2. Fuel system: Fires caused by leaks of vehicle fuel, engine oil, transmission fluid, power steering fluid, and other oils.

3. Exhaust system: Fires caused by contact between high-temperature exhaust pipes and combustible materials.

4. Braking system: Braking system failure or improper use leads to tire fires in large trucks.

5. Mechanical failure: Early water ingress into the engine or improper repairs, defects, etc., caused the connecting rod to break and pierce the cylinder wall, leading to engine oil leakage that ignited and caught fire.

6. Arson and other factors: vehicles ignited by arson, discarded embers, firecrackers, or external sources of fire.

7. Thermal runaway of high-voltage circuits in new energy vehicles: New energy vehicles contain multiple high-voltage components, wiring harnesses, connectors, etc. In addition to traditional fire causes, the causes of fires are more complex. When battery systems, power distribution systems, high-voltage wiring harnesses, etc. experience issues such as overcharging, overdischarging, internal short circuits, overheating, or damage caused by external impact, fire accidents may be triggered. Fires caused by electric vehicles themselves are generally the result of thermal runaway. After thermal runaway, the power battery will release toxic flammable gases, making combustion and explosion accidents likely.

4. Life-saving skills that vehicle owners should know and master.

A small flame can start a great fire; prevention is key. Fire safety is of utmost importance, and protecting our homes depends on everyone.

1. Regularly service and maintain the vehicle: In accordance with the requirements of the vehicle owner's manual, conduct comprehensive periodic maintenance of the vehicle, including inspection of the electrical system, fuel system, and mechanical components. Replace aged and damaged parts in a timely manner to ensure the vehicle remains in good operating condition.

2. Refuse unauthorized modifications: Do not modify the vehicle's electrical circuits, fuel system, or other components without authorization. If modifications are truly necessary, be sure to choose a professional modification shop and ensure that the modification plan will not compromise the vehicle's safety performance.

3. Strictly prohibit the storage of flammable and explosive items in the vehicle: Do not leave lighters, perfume, hairspray, or other flammable and explosive items in the vehicle. If they must be carried, be sure to take them with you when leaving the vehicle to avoid leaving them inside for extended periods.

4. Pay attention to driving habits: avoid running the vehicle under high load for extended periods, especially in hot summer weather. If you notice any unusual odors, smoke, or other abnormalities from the vehicle, stop immediately to inspect it. Do not take chances and continue driving.

5. Equip with fire extinguishing equipment: Keep a qualified fire extinguisher in your vehicle and learn how to use it properly. At a critical moment, a fire extinguisher can be the key tool that saves your vehicle and your life.

5. Beware of Battery Explosions

When abnormal current and voltage, battery heating, deformation, electrolyte leakage, or pungent odors occur, be alert for battery explosions.

6. Safety Lawyer Reminder

Always keep a firm grasp of the red line of safety. General Secretary Xi Jinping emphasized, “Human life is paramount, and development must never come at the expense of people’s lives. This must be regarded as an insurmountable red line.” The prevention of vehicle fires starts with everyday details. Do not leave things to chance; earnestly carry out the maintenance and care of your vehicle each time, and navigate safely on the road ahead.