Electronic – What type of fire extinguisher do I need for lithium polymer batteries


I plan on using reasonably cheap powerbanks (like the Aukey Mini 3600mAh) with my own circuits, and – ideally – I'd like to have an appropriate fire extinguisher on hand in case I mess up.

I know that there's protection circuitry inside these things, but if there is a compact, cheap fire extinguisher that I can also use on LiPo batteries if the need arises, I'd like to get one.

This document claims that I do not need a class D fire extinguisher for Li-ion batteries, and that water or ABC will do (but also that you will need one for Lithium batteries – the non-rechargeable kind), but I'm not sure if that applies to lithium polymer as well. This Product Safety Datasheet for Energizer lithium polymer batteries doesn't inspire a lot of confidence.

Again, ideally this thing would be very small, easily available, and not too expensive.

Best Answer

I think a better way would be to isolate the fire, but there isn't much lithium in batteries.

Simple Guidelines for Using Lithium-ion Batteries

  • Lithium-ion batteries contain little lithium metal and in case of a fire they can be dowsed with water. Only lithium-metal batteries require a Class D fire extinguisher.

Lithium polymer batteries shouldn't be too different from regular lithium batteries.

  • Water interacts with lithium. If a Class D extinguisher is not available to douse a lithium-metal fire, only pour water to prevent the fire from spreading.

  • For best results dowsing a Li-ion fire, use a foam extinguisher, CO2, ABC dry chemical, powdered graphite, copper powder or soda (sodium carbonate) as you would extinguish other combustible fires. Reserve the Class D extinguishers for lithium-metal fires only.

  • If the fire of a burning lithium-ion battery cannot be extinguished, allow the pack to burn in a controlled and safe way

  • Be aware of cell propagation as each cell might be consumed on its own time table when hot. Place a seemingly burned-out pack outside for a time.

Another good way is fire isolation get some bricks or cinder blocks and make a flame "container", if you mess up the heat will go into the brick slowly.