Lithium-Ion Batteries and Flooding Risks 

With the growing use of electric vehicles, mobility devices (such as scooters, hoverboards, and wheelchairs), and other equipment powered by rechargeable batteries, it is essential to recognize the fire risks these devices pose when exposed to water. Lithium-ion batteries, in particular, are highly vulnerable during flooding – especially in saltwater. Saltwater intrusion accelerates internal corrosion, which can cause short circuits. These short circuits may ignite battery cells, creating fire and explosion hazards that can occur immediately or even several hours to days after the flooding event.

Short Circuits and Corrosion

• Saltwater acts as a strong conductor, creating pathways for electrons that can cause rapid heating and potential ignition.
• The corrosive nature of saltwater damages the internal components of the battery, forming conductive “bridges” that can short-circuit the cells even after the water has dried. 

Thermal Runaway

Heat generated from short circuits can trigger thermal runaway, a chain reaction where cells rapidly overheat.

• Thermal runaway may lead to fires or explosions.
• These fires are extremely intense, can burn underwater, and release toxic, flammable gases. 

Delayed Ignition

• Corrosion damage inside the battery may cause fires to ignite hours—or even days—after the flood exposure.
• This means batteries remain hazardous until they are properly handled and disposed of. 

Additional Hazards

• Toxic Gas Release: Burning lithium-ion batteries emit dangerous gases harmful to breathe.
• Difficult to Extinguish: Standard water extinguishers are often ineffective; specialized Class D or foam extinguishers are required.
• Environmental Contamination: Improper disposal of flood-damaged batteries can harm the environment. 

Safety Recommendations

• Relocate Batteries: Move batteries and devices to higher ground if flooding is expected.
• Disconnect Devices: Unplug from charging stations and remove batteries if exposed to floodwater.
• Do Not Charge: Never attempt to charge or use batteries that have been submerged.
• Dispose Properly: Follow local hazardous waste disposal guidelines.
• Seek Professional Help: Contact the fire department or the device manufacturer for safe handling and disposal advice.