In his second appearance on this show, Paul Rogers answers a listener question that was sent to us from Captain Rich Nudd. Paul discusses the gasses liberated and the firefighting aspects of dealing with this type of emergency.
Complete Show Notes
00:45 Listener Question
- “Here in Las Vegas, we’re seeing an increase in the installation of lithium-ion battery packs (LG, Mercedes, and Tesla) as backup power for solar power systems. These systems have a small amount of elemental lithium in them. We’re trying to obtain information regarding which toxic gasses are released when these units burn or decompose in the heat of fire, but we haven’t been able to find any legitimate information. Do you have any experience with these units or know of a reliable source?”
2:05 Re-Introduction to Paul Rogers
- Currently a lieutenant in the New York City fire department assigned to a special project dealing with energy storage systems for the past 5 years
- Deals with manufacturers, codes, standards, and operations surrounding any batteries used in energy storage systems
3:15 Question #1: What Are the Major Toxic Gasses Found in LI Batteries?
- Testing done in Australia showed that some hydrogen fluoride was being produced by lithium-ion batteries
- The test was performed in an inert atmosphere, though, which changes the whole dynamic of the smoke signature because the battery wasn’t exposed to open air
- Testing is often performed in inert atmospheres because it makes it easy to identify all of the different gasses the batteries produce – they aren’t being moved around by the wind and air currents
- Keep in mind that the battery can be undergoing heat reactions deep inside the cell that you can’t see from the surface – can lead to a thermal runaway, where the whole module goes up in flames
- Lithium ion has many different chemistries within the actual lithium-ion family (i.e. lithium-ion cobalt oxide) – each one of these can produce different gasses
- A new UL testing standard is in the works for thermal propagation – designed to provide data to the authority having jurisdiction (AHJ) to make it easier to deal with burning/faulty batteries
11:40 Question #2: Which PPE Should We Wear Around Battery Fires?
- You’ll see the same gasses you see with structural fires, but there are higher levels of heat since they have stored energy inside of them
- Most fire departments want to clean their gear after every single fire, which is a major undertaking
13:55 Question #3: What’s the Suggested Extinguishing Medium for LI Battery Fires?
- NFPA 855 recommends proper extinguishing agents based on the chemistry of the substance – this isn’t out yet, but it will be in the near future
- New York City fire department and NFPA both suggest using water at a safe distance with lithium-ion battery fires – keep your distance to avoid electrical leakage coming back
- Remember that water becomes more conductive the moment you add something to it – this is a concern
- Foam is more conductive than water, and it also doesn’t have as much of a cooling capacity – we need water to absorb the high heat being put out from the batteries
16:35 Question #4: Is the Runoff from Fighting Battery Fires a Hazmat Issue?
- Water runoff will be corrosive, but keep in mind that we deal with this issue at any other type of fire
- Data shows that the water runoff from battery fires is no different than the runoff from structural fires
- It’s almost impossible to capture all the water needed to put out a large-scale energy storage system fire
- There aren’t really any instances where batteries in electric cars are catching on fire, so that’s not much of a concern – manufacturers are getting good at refining the technology
20:35 Question #5: What’s the Best Detection Technology for Testing Turnouts After a Fire and the Entire Area Prior to Overhaul?
- We want to eliminate overhaul on any kind of energy storage system – this is because it leaves stranded energy behind that could seriously hurt a responder
- Check out NFPA 1971, which is the bunker gear standard – Paul definitely suggests wearing bunker gear for the duration (even if you don’t touch the actual battery itself)
- GC-MS (gas chromatography-mass spectrometry) probably won’t be able to tell you how high the heat was and whether it compromised the integrity of the bunker gear
- You’ll need to send the PPE out to a testing lab to get the best results – it’s very difficult to reliably test anything in-house
25:20 Question #6: What Happens if the Battery Fire Reignites?
- Re-ignition may be the result of not enough water getting into the module to relieve the heat within the cells
- Heat reactions can continue, even at a slow pace – if you leave, though, they’ll increase because there’s no more water available
- Electrolyte inside the cell itself can vaporize if it gets too hot – this can release a flammable cocktail that’s far more dangerous than any fire
- Your biggest concern should always be explosion – make sure you’re getting the smoke and exhaust out of the area
- Always be on high alert if the battery is very hot but isn’t on fire – assume it’s an explosion hazard and that it’s releasing a dangerous flammable electrolyte
30:50 Question #7: What Are Our Post-Fire Electrical Concerns?
- Firefighters aren’t electricians, so we should always be concerned with and aware of the dangers surrounding electricity
- Incident commander should get experts on-scene to help us get batteries out of the building in a safe and effective manner
Have a question? Send an email to firstname.lastname@example.org or leave a message on our Haz Mat Guys comment hotline: 843-628-1484
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