EV Battery Fires: The Facts, the Risks and What to Do

How common are EV fires?

Analyses of fire-service and insurance data in several countries have consistently found that battery electric cars catch fire less often per vehicle than petrol or diesel cars — in some studies several times less often. A petrol car carries tens of litres of a highly flammable liquid and a hot engine; an EV battery is sealed, monitored and protected. Because EV fires are rarer and newer, each one gets far more coverage, which distorts the perception.

Why battery fires are different

The concern with lithium-ion batteries is 'thermal runaway': if a cell is damaged, overheated or overcharged, a chemical reaction can begin that heats neighbouring cells, which can spread through the pack. These fires are intense, produce toxic smoke, can take a long time to fully extinguish and occasionally reignite hours later. Modern packs are designed with cell isolation, cooling and venting to slow or prevent that spread, and the battery management system stops charging long before a cell is overstressed.

The real causes

• Severe physical damage to the pack — a major collision or striking heavy debris.
• Manufacturing defects in cells (the reason behind most recalls).
• Water ingress after deep flooding, especially saltwater, which can corrode and short the pack days later.
• Poor-quality or damaged charging equipment and unsafe home wiring — a bigger factor for e-bikes and scooters with cheap chargers than for cars.
• Extreme overheating combined with a fault.

Reducing the risk

1. Act on manufacturer recalls promptly — they are usually about battery safety.
2. Use only certified chargers and cables, and have home charging installed professionally.
3. Have the battery inspected after any significant underbody impact or after driving through deep water.
4. Don't park a car with known battery damage in or next to a building.
5. For e-bikes and scooters: never charge on an escape route, use the original charger, and don't leave them charging unattended overnight — this is where most residential battery fires occur.

If a fire starts

• Get everyone out and well away — the smoke is toxic. Do not try to fight a battery fire yourself.
• Call the emergency services and tell them it is an electric vehicle so they bring the right equipment.
• If the car is charging and it is safe to do so, use the charger's emergency stop.
• Never use water on a live high-voltage battery yourself; leave it to the fire service, who use large volumes of water or specialist methods.

Perspective: you are statistically safer from fire in an EV than in a petrol car. The precautions above address the small number of situations that account for almost all EV fires.