Extinguishing of lithium fires
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- Опубликовано: 21 авг 2024
- Scenario: Li polymer cells activated by overcharge of a single cell in a 4 series connected cell arrangement.
Fire of Li cells could be effectively extinguished. The duration of fire period (open flames) could be significantly shortened (from 77 to 7 seconds) by the aerosol fire extinguisher. It could be demonstrated that the fire spreading can be avoided or significantly reduced by the use of the fire extinguisher. Extinguishing could save 2 out of 4 batteries from catching fire. 
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I did not see any extinguisher applied to the fire. As to Lith-ex fire extinguisher, I don't know of any place I could buy it readily in USA. I wish I knew what product you were supposedly promoting.
Secondary (rechargeable) lithium batteries do not use lithium metal (as the company confirmed), they use lithium salts which are not unstable in air/water, at least not to any flammable degree. Primary (non-rechargeable) batteries do use lithium metal and are a different story.
Once a secondary cell goes off, I have serious doubts that anything could extinguish it since it is burning its own oxygen and hydrogen. What is a powder extinguisher going to do? The only thing that can be done is to cool the batteries to prevent the thermal runaway in other cells.
In this test I don't see that happening. While it's nice that there's no flame, the cells all still went off, so it seems like the heat was still there, and may not even be reduced since they all went off fairly quickly.
Thank's for the helpful advice I'm building something with a built to stop the inevitable failure and minimizing damage of that situation design
I'd like some more imput but I'm trying design around fail safes I'm currently sketching the housing and lines
Intriguing and scary stuff!
How about adding a bit of audio commentary
What do you mean by aerosol extinguisher? Be more specific
What type of aerosol fire extinguisher is used in these cases? More importantly, if this happens to an RC hobbyist, i.e. not in a controlled environment, what's the best way to put it off?
Hi Nikolaos, it depends of the size of enclosure what type of unit is used. Our smallest unit is just 4 grams so we can also go in really small enclosures.
In RC cases it depends where you storage your batteries, we recommend aluminium or similar casing for them and put a aerosol unit inside the box when it can stop the fire inside the container.
@@SalgromTechnologies you didn't quite define what aerosol was used. Powdered aerosol? FM-200? Condensed aerosol? Bearded lady aerosol?
There obviously was useful residual extinguisher, as the last two batteries failed to flare, but without a recommended and tested specific agent, it's hard to specify for those of us who have larger than usual lithium ion battery stocks that are not commercial in nature and hence, on a serious budget.
@@spvillano lipos don't contain much lithium. Under 1 percent to be specific. What's burning is hydrogen and oxygen. Any powder extuingsher will work
@@sauerlandfpv5425 units I saw dismantled had a pyrophoric metal film inside, which reacted to water or air.
@@spvillano As far as I've learned is that the industry which make fire extinguishers are protective about there method's. As they want to sell the formulas. On some way understandable and the other way counter productive in safety first mentality. Capitalism first.
Anywho, I'm testing it on my own. As mentioned here and there, it produces some gasses Hydrogen, oxygen and some other toxic and non-toxic gasses.
With any combustion there's triangle if you didn't know yet. (Heat - oxygen - Fuel) if extinguishing is needed at least one of the three needs to be eliminated. While fuel (lithium) is not directly removable from heat and Oxygen, there is two solutions. Taking Oxygen and/or heat out off the equation. Therefore remove oxygen with solution of isolating it from fuel (lithium), example; suffocating lithium with poring sand or other medium similar to sand over it and/or cooling it down somehow.
Problem is with lithium is that it can violant react with water (H20).
So a fluid not based on water and is not flammable by heat itself.
So powder/large granules and/or foam will suffice. Taking in account the substance which to use are not flammable and/or combustible. (Milk powder is highly combustible on open flame or very high heat)
Moral of the story, most foam extinguisher supposedly work. Powder work too but not as effective. doesn't take heat away, especially "run-away heat". Gas (CO2) extinguisher doesn't help if the lithium battery isn't enclosed in a bowl type or full enclosure. Hope it helps people to rationalize and maybe some thought experiments.
where can you buy these stuff?