Lithium-Ion Battery and Electric Vehicle Fires
Battery fires that self-generate heat, cannot be extinguished by conventional means, and carry re-ignition risk hours to days after apparent suppression — treat as hazmat from dispatch.
What This Incident Looks Like
Lithium-ion battery fires are self-sustaining exothermic reactions, not fires in the conventional sense. Once thermal runaway begins in one cell, the heat it generates triggers the same reaction in adjacent cells, and this cascade cannot be stopped by water, foam, or CO2 once it's fully established. Suppression water cools the exterior and slows propagation between cells; it does not stop the internal chemical reaction driving the whole event. The fire can re-ignite minutes, hours, or even days after it appears fully extinguished, which is why EVs with confirmed battery involvement must never be stored in enclosed structures during the re-ignition watch period.
The hazmat dimension here is primary, not secondary to the fire problem. Thermal runaway vents hydrogen fluoride (HF), hydrogen cyanide, carbon monoxide, and volatile organic compounds. HF carries an IDLH of just 30 ppm and causes delayed pulmonary injury — responders may feel completely fine on scene and develop symptoms hours later, well after they've left. Water runoff from EV suppression carries heavy metals and HF, making it contaminated water that must be treated and reported as such, not just wet pavement. SCBA is mandatory for all personnel operating in the smoke plume for the entire duration of the incident.
Recognition Clues
- An EV badge or charge port on the vehicle — dispatch should ask callers to identify vehicle type on any vehicle fire or MVA call, since this changes the response from the first radio transmission
- Popping, hissing, or crackling sounds from the undercarriage; visible off-white or gray smoke from below the vehicle floor; battery pack venting visible at the rocker panels
- Thermal imaging shows persistent heat in the undercarriage floor area even after visible flames have been knocked down
- An e-bike, e-scooter, or portable battery device involved in a structure fire — the battery pack is usually visible as a rectangular or cylindrical black module
- An Energy Storage System (ESS) cabinet alarm at a commercial, industrial, or utility site
First-Due Actions
- Treat as hazmat from dispatch — SCBA on before exiting the apparatus, upwind staging, and a 50-foot initial isolation minimum for battery fires
- Identify battery involvement with thermal imaging before committing a hoseline — if the undercarriage or pack reads hot, plan for large water volumes (3,000+ gallons) and an extended operation
- Apply water to cool the exterior and slow thermal runaway propagation — secure a hydrant or tender supply early, since suppression may require 30 to 60+ minutes of continuous flow
- Establish a re-ignition watch protocol before releasing the scene — notify tow operators in writing that the vehicle cannot go to enclosed storage
- Request the hazmat team early if HF exposure or mass-victim risk exists, and notify the receiving hospital of possible HF exposure before patient transport
Do Not
- Do not store a vehicle with battery involvement in any enclosed structure during the re-ignition watch period — minimum 24 to 48 hours in open air with water access
- Do not cut into or dismantle a damaged battery pack — mechanical damage triggers additional cell failures and creates an electrocution hazard on top of the fire risk
- Do not release crews from SCBA while still in the smoke plume — HF and CO exposure is possible downwind even after visible flames are out
- Do not allow runoff water to enter storm drains without notification to environmental authorities — contaminated runoff from an EV fire is a regulatory event, not just cleanup
Related References
Official Sources
Official sources are linked for verification. This page is a firefighter training reference, not legal or medical advice.