Recent flooding from hurricanes Helene and Milton in late 2024 caused extensive damage across the Southeast, leading to numerous electric vehicles and battery-operated devices catching fire due to exposure to saltwater.

In total, 11 electric cars and 48 lithium-ion batteries ignited after being submerged in salty floodwaters, with some fires spreading to nearby residential properties.

Saltwater significantly increases the risk of battery fires because it is highly conductive, which can lead to short circuits and rapid corrosion within the battery.

The risk of fire is further heightened by a phenomenon known as thermal runaway, where a chain reaction within the battery cells releases heat and can be exacerbated by saltwater exposure.

Battery enclosures may not be completely waterproof during prolonged immersion, allowing water to enter through seals and ports, which can lead to delayed thermal runaway events.

Even fully discharged lithium-ion batteries can retain a voltage that may lead to current flow and chemical reactions, creating fire hazards long after flooding has occurred.

Experts advise electric vehicle owners to take precautions during flooding by moving vehicles to higher ground and avoiding submersion in saltwater, treating flooded vehicles as potential fire hazards until they are professionally inspected.

If an electric vehicle has been submerged, it should not be charged or operated and must be placed in an open area away from other properties until assessed for safety by professionals.

When lithium-ion batteries catch fire, they emit toxic fumes and burn intensely, making them challenging for firefighters to extinguish, often requiring them to let the fire burn out naturally.