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 — once thermal runaway begins in a cell, the heat it generates triggers the same reaction in adjacent cells. This cascade cannot be stopped by water, foam, or CO2 once established. Suppression water cools the exterior and slows propagation; it does not stop the internal chemical reaction. The fire can re-ignite minutes, hours, or days after it appears extinguished. EVs with battery involvement must never be stored in enclosed structures during the re-ignition watch period.
The hazmat dimension is primary, not secondary. Thermal runaway vents hydrogen fluoride (HF), hydrogen cyanide, carbon monoxide, and volatile organic compounds. HF has an IDLH of 30 ppm and causes delayed pulmonary injury — responders may feel well at the scene and develop symptoms hours later. Water runoff from EV suppression carries heavy metals and HF; it is contaminated water and must be treated as such. SCBA is mandatory for all personnel operating in the smoke plume.
Recognition Clues
- EV badge or charge port on the vehicle — dispatch should ask callers to identify vehicle type on any vehicle fire or MVA call
- Popping, hissing, or crackling sounds from the undercarriage; visible off-white or gray smoke from below the vehicle floor; battery pack venting visible at rocker panels
- Thermal imaging shows persistent heat in the undercarriage floor area even after visible flames are knocked down
- E-bike, e-scooter, or portable battery device involved in structure fire — battery pack usually visible as rectangular or cylindrical black module
- Energy Storage System (ESS) cabinet alarm at commercial, industrial, or utility site
First-Due Actions
- Treat as hazmat from dispatch — SCBA on before exiting apparatus, upwind staging, 50-foot initial isolation minimum for battery fires
- Identify battery involvement with thermal imaging before committing a hoseline — if undercarriage or pack is hot, plan for large water volumes (3,000+ gallons) and extended operation
- Apply water to cool the exterior and slow thermal runaway propagation — secure a hydrant or tender supply early; suppression may require 30-60+ minutes of continuous flow
- Establish a re-ignition watch protocol before releasing the scene — notify tow operators that the vehicle cannot go to enclosed storage; document in writing
- Request hazmat team early if HF exposure or mass-victim risk exists; notify 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 24-48 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
- Do not release crews from SCBA while 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 is a regulatory event
Related References
Official Sources
Official sources are linked for verification. This page is a firefighter training reference, not legal or medical advice.