Because lithium-ion batteries are difficult to extinguish when on fire, how do emergency personnel deal with the situation?

• A. Apply standard fire extinguisher
• B. Shut off power and ventilate
• C. Flood the battery compartment with water
• D. Let it burn out

Answer: (C)

Lithium-ion battery fires are driven by rapid heat buildup inside the pack, so removing heat is the priority. When cells overheat, they can enter thermal runaway and spread the fire to other cells. Water works well because it absorbs a lot of heat, cooling the battery pack quickly and slowing or stopping the runaway reaction, which also helps prevent reignition as the pack vents. Flooding with water can also help dilute and carry away flammable electrolyte vapors, reducing danger to responders. Standard fire extinguishers don’t provide the same rapid cooling and may be ineffective on such hot, contained fires, and simply letting it burn out is highly dangerous. If possible, shutting off power and ventilating are useful steps, but the most reliable way to control a Li‑ion battery fire is to flood the area with water to cool the cells.