Why are new energy vehicles prone to fire?

Why are new energy electric vehicles prone to fire? What is the reason behind it? Let’s explore it now!

PART/01 Battery thermal runaway

Battery thermal runaway is the root cause of new energy electric vehicle fires, and the main causes of battery thermal runaway are: mechanical abuse (collision, etc.), electrical abuse (overcharging, internal short circuit, etc.) and thermal abuse. In the charging process, as long as the temperature monitoring and heat dissipation measures are slightly wrong, battery thermal runaway may occur, which will cause a fire.

Take the accident that occurred at a charging station in Wenzhou on September 29, 2023 as an example. An electric car that was charging suddenly smoked and exploded, causing damage to many vehicles. The investigation found that the battery temperature rose abnormally during the charging process, which caused thermal runaway and eventually caused a fire.

PART/02 Electrical circuit failure

The electrical circuit of new energy electric vehicles is a key part to ensure the safe operation of the vehicle. Because the vehicle is exposed to complex working conditions for a long time, the electrical circuit is prone to insulation damage, circuit aging, loose connectors and other faults. If such a fault causes a short circuit, the sudden increase in current will cause the circuit temperature to rise sharply, which may lead to a fire accident.

On October 5, 2024, an electric car in Zhangzhou caught fire at the door of a car repair shop. In less than 20 minutes, the entire car was engulfed by fire. It was found that the cause of the fire was an electrical circuit failure.

PART/03 Influence of external heat sources

External heat sources are also an important factor in causing fires in new energy electric vehicles, and these heat sources are relatively common in daily life.

For example, summer sun exposure can easily lead to high temperatures in the car, which can easily induce battery thermal runaway or circuit failure; cigarette butts, lighters and other items left in the car may also cause fires due to local overheating.

At the end of November 2024, a new energy vehicle in Huzhou City, Zhejiang Province suddenly caught fire while parked on the roadside. After investigation, the cause of the fire was that the owner accidentally left the lighter in the gap of the driver’s seat slide rail. When the seat was adjusted, the lighter switch was squeezed and triggered, igniting the surrounding combustible materials and eventually causing the vehicle to catch fire.