safety physical_safety ai_generated true

AI advises using a Class A fire extinguisher (water or foam) on a lithium-ion battery fire, or tells someone to smother the fire with a blanket

ID: safety/lithium-ion-fire-extinguisher

Also available as: JSON · Markdown · 中文
80%Fix Rate
90%Confidence
1Evidence
2024-09-20First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
NFPA 18 Standard on Wetting Agents v2023 active — — —
UL 1642 Lithium Batteries v5 active — — —
IEC 62133-2:2017 active — — —

Root Cause

Lithium-ion battery fires are Class B (flammable liquid) and Class D (combustible metal) hazards; water or foam can cause thermal runaway escalation due to lithium metal reactivity with water, and smothering with a blanket does not cool the battery cells, allowing internal short circuits to reignite.

generic

中文

锂离子电池火灾属于B类（易燃液体）和D类（可燃金属）危险；水或泡沫会因锂金属与水的反应导致热失控升级，而用毯子窒息无法冷却电池单元，允许内部短路重新点燃。

Official Documentation

https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=18

Workarounds

  1. 80% success Use a Class D extinguisher specifically rated for lithium-metal fires (e.g., Lith-X, Met-L-X, or copper powder extinguishers). For lithium-ion (not lithium-metal), a Class B extinguisher (dry chemical, CO2) may suppress flames but cooling is critical; deploy a thermal imaging camera to monitor for hotspots. 
    Use a Class D extinguisher specifically rated for lithium-metal fires (e.g., Lith-X, Met-L-X, or copper powder extinguishers). For lithium-ion (not lithium-metal), a Class B extinguisher (dry chemical, CO2) may suppress flames but cooling is critical; deploy a thermal imaging camera to monitor for hotspots.
  2. 75% success For small lithium-ion battery fires in devices (e.g., laptops, phones), submerge the burning device in a bucket of water or sand if safely accessible, or place it in a fireproof container (e.g., Lipo Sack) and move outdoors. Water submersion is effective for small packs because it cools cells and prevents thermal runaway propagation. 
    For small lithium-ion battery fires in devices (e.g., laptops, phones), submerge the burning device in a bucket of water or sand if safely accessible, or place it in a fireproof container (e.g., Lipo Sack) and move outdoors. Water submersion is effective for small packs because it cools cells and prevents thermal runaway propagation.
  3. 85% success Follow NFPA 18A: use a water mist or wetting agent specifically designed for lithium-ion fires (e.g., F-500 Encapsulator Agent) which cools and encapsulates the electrolyte, reducing reignition risk. This is standard in electric vehicle fire response. 
    Follow NFPA 18A: use a water mist or wetting agent specifically designed for lithium-ion fires (e.g., F-500 Encapsulator Agent) which cools and encapsulates the electrolyte, reducing reignition risk. This is standard in electric vehicle fire response.

中文步骤

  1. 使用专门用于锂金属火灾的D类灭火器（例如Lith-X、Met-L-X或铜粉灭火器）。对于锂离子（非锂金属），B类灭火器（干粉、CO2）可能抑制火焰，但冷却至关重要；部署热成像相机监控热点。
  2. 对于小型锂离子电池设备火灾（如笔记本电脑、手机），如果安全可及，将燃烧的设备浸入一桶水或沙子中，或放入防火容器（如Lipo Sack）并移至室外。对于小电池组，水浸有效，因为它能冷却电池并防止热失控传播。
  3. 遵循NFPA 18A：使用专门设计用于锂离子火灾的水雾或润湿剂（例如F-500封装剂），它能冷却并封装电解液，降低复燃风险。这是电动汽车火灾响应的标准做法。

Dead Ends

Common approaches that don't work:

  1. 90% fail

    Water reacts with lithium salts and organic electrolytes, producing flammable hydrogen and increasing thermal runaway.

  2. 85% fail

    Lithium-ion fires are self-sustaining due to internal chemical reactions; oxygen is not required for combustion.

  3. 60% fail

    CO2 displaces oxygen but has minimal cooling effect; battery cells can reach >500°C internally.