Not to cause any alarm but create awareness about the current tech we love.

This link was shared on a watsaap groep by a member. A very informative channel.

Very interesting, and frightening...

Can someone perhaps elaborate on the chemical reaction that was mentioned in the video, that LFP generates about 50% hydrogen - is that 50% of the battery mass, or is half of the gasses that are produced in such a meltdown reaction hydrogen? Either way, not good... So, what can one do to reduce the risk of a large hydrogen explosion...

Would it be better to have a small volume explosion (say I flimsy small container that just covers the batteries) that could explode with a reasonably small force rather than having a garage full of hydrogen gas created by having 2, or 4, open batteries fixed to your garage wall... Hmm, will have to think about that.

15 hours ago, HennieL said:

Very interesting, and frightening...

Can someone perhaps elaborate on the chemical reaction that was mentioned in the video, that LFP generates about 50% hydrogen - is that 50% of the battery mass, or is half of the gasses that are produced in such a meltdown reaction hydrogen? Either way, not good... So, what can one do to reduce the risk of a large hydrogen explosion...

Would it be better to have a small volume explosion (say I flimsy small container that just covers the batteries) that could explode with a reasonably small force rather than having a garage full of hydrogen gas created by having 2, or 4, open batteries fixed to your garage wall... Hmm, will have to think about that.

It is not specified if by mass or volume. I think the take away is 4% hydrogen and x% oxygen. Also that the battery not sealed good enough to allow the hydrogen to escape. As indicated the toolbox also exploded indicating that it was also filled with hydrogen.

Very interesting that this explosion was not covered in the news as few of these disasters are public knowledge. His position provides him with investigations and he then shares it as part of training.

Another important thing is that it is not know what effect inhaling the gasses have on human beings. He just says it took the owner 1 year to recover after inhaling the gasses after the explosion.

12 minutes ago, Scorp007 said:

Also that the battery not sealed good enough to allow the hydrogen to escape. As indicated the toolbox also exploded indicating that it was also filled with hydrogen.

Yes, I noted that, and it actually triggered the thought that it might be better to install a small "container" closely around the battery, and rather let that "explode" than having a whole garage or outbuilding explode... something flimsy enough to vent without creating enough force to damage more than the batteries and container. I already have a polystyrene sheeting "cover" around the batteries to isolate them from the winter cold - see this old post for more details: https://powerforum.co.za/topic/32653-heating-lifepo4-batteries-in-winter-cooling-in-summer/ and could easily seal it to create an air-tight "chamber"...

27 minutes ago, Scorp007 said:

Another important thing is that it is not know what effect inhaling the gasses have on human beings. He just says it took the owner 1 year to recover after inhaling the gasses after the explosion.

Yes, perhaps we should do some further investigation regarding the actual incident, and more specifically regarding the injuries he was treated for. Any medical doctors on this Forum that could give input?

OK, I had a long "chat" to Google AI about this:

"Because LFP burns cooler than regular lithium-ion, it produces a massive amount of unburned chemical compounds. Inhaling this vapor is extremely hazardous and causes severe, immediate damage to the human body.

Here is a breakdown of the primary "bad stuff" inside that cloud and its specific effects on a person:

1. Carbon Monoxide (CO)

• What it is: An odorless, colorless gas that is produced in massive quantities during LFP incomplete combustion.

• The Effect: It binds to the hemoglobin in your red blood cells 200 times more effectively than oxygen, starving your brain and heart. Inhalation leads to immediate dizziness, confusion, severe headache, unconsciousness, and asphyxiation.

2. Hydrogen Fluoride (HF) Gas

• What it is: This is the most dangerous acute toxin in the cloud, created when the fluorinated polymer binders (PVDF) and the lithium salt electrolyte (LiPF6) inside the battery break down under extreme heat.

• The Effect: When HF gas touches moisture—like the sweat on your skin, the film on your eyes, or the lining of your lungs—it immediately turns into Hydrofluoric Acid. It causes deep, agonizing chemical burns that destroy tissue. More dangerously, it is absorbed through the skin and lungs into the bloodstream, where it aggressively leaches calcium and magnesium out of your bones and blood, which can cause sudden, fatal cardiac arrest hours after exposure.

3. Vaporized Organic Carbonates

• What it is: This makes up the bulk of the visible "white cloud." Batteries use liquid organic solvents like Dimethyl Carbonate (DMC), Diethyl Carbonate (DEC), or Ethylene Carbonate (EC) to carry the electrical charge between cells. The heat vaporizes these liquids into a heavy mist.

• The Effect: These solvents are highly irritating, volatile organic compounds (VOCs). Inhaling them causes an immediate choking reflex, blinding stinging in the eyes, burning in the throat, and severe chemical pneumonitis (fluid buildup in the lungs, effectively causing a person to "drown" internally from the chemical irritation).

4. Phosphoric Acid & Lithium Aerosols

• What it is: As the iron-phosphate cathode structure breaks down, fine particulate matter and phosphoric compounds are ejected into the air under pressure.

• The Effect: These create an intensely corrosive soot. If inhaled, it causes immediate, permanent scarring of the respiratory tract.

Summary of Human Impact

If a person walks into a garage or attic filled with this unignited white gas without a professional Self-Contained Breathing Apparatus (SCBA), they will be incapacitated within seconds. The combination of oxygen deprivation (CO), severe internal chemical burns (HF), and intense respiratory choking (Carbonates) means escaping a room filled with this gas quickly becomes physically impossible."

Bad stuff 🥵😵

2 hours ago, HennieL said:

Yes, I noted that, and it actually triggered the thought that it might be better to install a small "container" closely around the battery, and rather let that "explode" than having a whole garage or outbuilding explode... something flimsy enough to vent without creating enough force to damage more than the batteries and container. I already have a polystyrene sheeting "cover" around the batteries to isolate them from the winter cold - see this old post for more details: https://powerforum.co.za/topic/32653-heating-lifepo4-batteries-in-winter-cooling-in-summer/ and could easily seal it to create an air-tight "chamber"...

Yes, perhaps we should do some further investigation regarding the actual incident, and more specifically regarding the injuries he was treated for. Any medical doctors on this Forum that could give input?

I did have some vented cells but the bit of liquid was below the cells that were lying flat in the box and it took up all the space. I could see some swallen cells even at the time of getting the battery. Only when I took the time to strip everything out of the box could one see the liquid that were partially absorbed by a plastic sheet under the cells. As the cells were spot welded one had to remove all cells.

Stripping took place outside in case there were gasses. Liewer bang Jan as dooi Jan.

It will be good to know if the battery is disconnected after venting and signs of this venting if the gasses can cause health issues.

The follow up:

Some important information about LFP thermal runaway from Battery University.

https://www.batteryuniversity.com/article/bu-304a-safety-concerns-with-li-ion/

I note that the links from @Scorp007 original post, and from @Thunderdolt follow-up post have disappeared - perhaps the problem is only on my side, but would you guys please paste the links (url's) to the videos again just for future reference should anyone else like to watch these videos as well...

Thanks.

13 hours ago, TaliaB said:

Some important information about LFP thermal runaway from Battery University.

https://www.batteryuniversity.com/article/bu-304a-safety-concerns-with-li-ion/

Thanks for this link. I have learned a lot from Battery University over the years, but this article is a bit disappointing (obviously not blaming you for this...)

I've just read through the article, and unfortunately the author concentrates on small batteries (he refers to cell phone batteries, and "industrial batteries" (such as used in power tools), and makes a few statements about EV batteries (such as: "statistics shows that EVs produce fewer fires compared to vehicles with the internal combustion engine (ICE) per billion kilometers driven"), but I could not find any in-depth evaluation of solar battery usage or risks...

The article is also concentrating only on "putting out the fire", but do not address the very high risk associated with the out-gassing of very nasty chemicals when the cells rupture and/or burn (as described in detail in the original video, and in the summary that I posted above...), apart from one piece of advice: "With all battery fires, allow ample ventilation while the battery burns itself out". In fact, one of the statements is quite contradictory: "Increasingly, experts advise using water even with large Li-ion fires. Water lowers combustion temperature but is not recommended for battery fires containing lithium-metal".

As this article demonstrates, the highly toxic gasses venting from a runaway lithium battery fire is not well known - and neither is the risk of an explosion resulting from the accumulation of hydrogen and oxygen gasses when the batteries are burning in a small contained environment, as the videos posted by @Scorp007 and @Thunderdolt in this thread reveals.

On 2026/05/18 at 1:31 PM, HennieL said:

OK, I had a long "chat" to Google AI about this:

"Because LFP burns cooler than regular lithium-ion, it produces a massive amount of unburned chemical compounds. Inhaling this vapor is extremely hazardous and causes severe, immediate damage to the human body.

Here is a breakdown of the primary "bad stuff" inside that cloud and its specific effects on a person:

1. Carbon Monoxide (CO)

• What it is: An odorless, colorless gas that is produced in massive quantities during LFP incomplete combustion.

• The Effect: It binds to the hemoglobin in your red blood cells 200 times more effectively than oxygen, starving your brain and heart. Inhalation leads to immediate dizziness, confusion, severe headache, unconsciousness, and asphyxiation.

2. Hydrogen Fluoride (HF) Gas

• What it is: This is the most dangerous acute toxin in the cloud, created when the fluorinated polymer binders (PVDF) and the lithium salt electrolyte (LiPF6) inside the battery break down under extreme heat.

• The Effect: When HF gas touches moisture—like the sweat on your skin, the film on your eyes, or the lining of your lungs—it immediately turns into Hydrofluoric Acid. It causes deep, agonizing chemical burns that destroy tissue. More dangerously, it is absorbed through the skin and lungs into the bloodstream, where it aggressively leaches calcium and magnesium out of your bones and blood, which can cause sudden, fatal cardiac arrest hours after exposure.

3. Vaporized Organic Carbonates

• What it is: This makes up the bulk of the visible "white cloud." Batteries use liquid organic solvents like Dimethyl Carbonate (DMC), Diethyl Carbonate (DEC), or Ethylene Carbonate (EC) to carry the electrical charge between cells. The heat vaporizes these liquids into a heavy mist.

• The Effect: These solvents are highly irritating, volatile organic compounds (VOCs). Inhaling them causes an immediate choking reflex, blinding stinging in the eyes, burning in the throat, and severe chemical pneumonitis (fluid buildup in the lungs, effectively causing a person to "drown" internally from the chemical irritation).

4. Phosphoric Acid & Lithium Aerosols

• What it is: As the iron-phosphate cathode structure breaks down, fine particulate matter and phosphoric compounds are ejected into the air under pressure.

• The Effect: These create an intensely corrosive soot. If inhaled, it causes immediate, permanent scarring of the respiratory tract.

Summary of Human Impact

If a person walks into a garage or attic filled with this unignited white gas without a professional Self-Contained Breathing Apparatus (SCBA), they will be incapacitated within seconds. The combination of oxygen deprivation (CO), severe internal chemical burns (HF), and intense respiratory choking (Carbonates) means escaping a room filled with this gas quickly becomes physically impossible."

Bad stuff 🥵😵

Thanks a lot for these facts. Now we know for sure to discard and leaked cell from lithium.

Very scary indeed to have in our homes/yacht or caravan.

Incident closer to home. In all of the information gathered on this post what is or was the root cause of the thermal runaway events? Take for instance the sealed container, what was the temprature of the battery packs inside the non ventilated container or was it ventilated?? In all of the videos the exact cause of LFP failure is not disclosed or diffucult to pinpoint. What is the failure rate of LFP 1 out of 40 million ?

How to prevent thermal runaway in our domestic setups. Basically do not stress abuse or damage the cells apart from that nothing in life is certain misfortune lurkes in every corner of our lives in diffrent shapes and forms. All that we can do is to endeavor to be safe as humanly possible.

FIRE OPS SA

FIRE OPS SA - Batteries catch fire at Standard Bank offic...

“Fire Ops teams were dispatched at approximately 09:00, where they encountered an intense blaze inside a container housing two 300kWh lithium-ion battery racks,” said Koekemoer. “Despite nearly two ho

3 minutes ago, TaliaB said:

How to prevent thermal runaway in our domestic setups. Basically do not stress abuse or damage the cells apart from that nothing in life is certain misfortune lurkes in every corner of our lives in diffrent shapes and forms. All that we can do is to endeavor to be safe as humanly possible.

Wise words indeed - but there are unfortunately many in this industry that either don't know, or don't care because they don't know, of the risks associated with our solar power systems.

In my opinion, and based on my own experience gained as a "home user", the industry should drive for improvement in 4 main areas:

• Education: I thought that I was "reasonably" educated in the theory and application of PV systems (at least on a "home owner" level), but never knew about the substantial risk to life resulting from a thermal overload and rupture of a battery as a result of the highly toxic vapour released during such an event. At no time during my discussion with various sellers and installers of systems (whilst I was "shopping" for my system nearly 2 years ago) did ANYONE mention this chemical risk - and I'm sure that I am not alone in this... In my opinion, the manufacturers, suppliers and installers of lithium-ion batteries have a moral obligation to inform their (potential) clients of this danger - even though there is a very low risk of such an incident happening.

• Installation: Again, speaking from my own experience - my system was installed compliant with all the requirements of the SANS electrical code... Four massive isolators/fuses were installed between the two batteries and the busbar boxes to interrupt current either deliberately by being opened, or by blowout of the 250A fuses on both positive and negative wires leading to the busbars. The high-voltage DC from the PV panels leading to the inverter is routed through a dedicated DC distribution board (enclosed in it's own box) with surge protectors, fuses, and DC disconnection switches - all compliant with code... The problem (that became clear now that I've done an informed risk assessment), is that both the DC isolators from the batteries, the AC and DC DB boxes, and the trunking with all the fat DC cables in them, are all: a) made of plastic; and b) located directly above the batteries. Now, I've come to know the installer quite well during the installation, and neither he, nor the master electrician that issued the COC, were negligent in anything electrical - but these DB boxes and isolators were installed in the worst possible place to actually reach them in case of emergency if a battery did rupture and started off-gassing, or was actually burning. This, I'm guessing, was as a result of not knowing and/or fully appreciating the inherent chemical and fire risks associated with these batteries! So, the installer (in my case) was not properly trained in these safety aspects by Industry (e.g. no warnings in the installation pamphlet supplied by the manufacturer of the batteries), and a "non-electrical" risk assessment was also not part of the COC inspector's duties...

• Design: Knowing what I now know, I would have included more passive fire protection measures, even though it would have increased the installation costs. I will certainly look into installing a "fire-proof" enclosure around my batteries with a "venting" chimney leading up from this enclosure, through the ceiling of my garage (where the system is installed), and through the gable wall, so that any out-gassing fumes can be safely vented away from the rest of my house - this should not be too expensive, and should at least protect the house, and it's inhabitants, from this very-small-chance-of-happening-but-with-extremely-serious-consequences event. Obviously, I would also not have allowed the disconnects and DB boxes to be installed close to, and above, the batteries - just to save on some cabling cost...

• Operation: Don't abuse the batteries! I've seen frequent statements on this Forum where people are "fast charging" their batteries at their maximum rated current, or regularly "deep discharging" the batteries until they cut off during loadshedding events, without any concern regarding the thermal and chemical stresses that such actions apply to the batteries. This is probably due to the industry marketing tactic to rate their batteries as "100% dischargeable", "fast charge enabled", etc. without adding at least a warning of potential consequences.

Well, that was a long one - but I think this matter warrants some detailed discussions by both "owner/users" and installers.

Edited May 26May 26 by HennieL
typo correction

1 hour ago, TaliaB said:

Incident closer to home. In all of the information gathered on this post what is or was the root cause of the thermal runaway events? Take for instance the sealed container, what was the temprature of the battery packs inside the non ventilated container or was it ventilated?? In all of the videos the exact cause of LFP failure is not disclosed or diffucult to pinpoint. What is the failure rate of LFP 1 out of 40 million ?

I seriously doubt that these were LFP. NMC type Lithium Ion, sure...

As for the 1st video in this thread, I saw lots of 18650 cells in the video, who has a LiFePO4 battery made up of 18650 Cells?

Will Prowse has a video addressing the LiFePO4 issue and it is supposedly a serious health hazard if the LiFePO4's should vent, however, the amount of failures of the LiFePO4 cells. or rather the lack of failures, indicates to me at least, that you should be aware of the possible hazard, but don't panic, if you have treated your cells well, did not drop them, did not over charge or discharge them, then the likelyhood of things hitting the fan is so low, that you should not over-sensationalise the very few failures that do occur, rather investigate why, if possible, the failure occurred, the 1st video in this thread, the battery with loads of 18650 cells, how was this put together by the manufacturer? If they have loads of parallel cells, which they presumably had, was each cell fused individually? etc.

I think for us homebrewers, 304 or 314Ah cells in 16S format with a decent BMS, we probably should be aware, but don't have to be unrealistically concerned about gassing, as long as we treat our batteries well.

I don't come near the 3.6V mark, heck I charge up to 55.2V (/16=3.450V per cell) and the lowest I've seen to far is 51.33V (/16=3.208V per cell), with maximum cell delta of 0.034V aka 34mV on my worst 304Ah battery in the last 33 days, the rest of them 15mV, 13mV and 12mV. Based on this, I believe that my cells won't vent and will carry on operating for many years into the future.

As it is, my batteries/inverters/MPPTs are all in the garage which is very well ventilated, chances of hydrogen or other gas accumulating is pretty much non-existant. If you have LiFePO4 batteries, obviously they probably should not be in your house, but the NMC type Lithium Ion batteries are the ones, I would be a lot more worried about.

Just to side track a bit... here's a link to a very informative YouTube video about variability found in so-called 18650 lithium-ion batteries (unknown if there were any LiFePO4 chemistry ones tested):

https://www.youtube.com/watch?v=-Y23nfAOiXQ

And here's a link to the downloadable scientific study that this video is based on:

The Lumafield Battery Quality Report

Download Lumafield’s Battery Quality Report on 18650 lithium-ion cells: CT-based metrics, defect rates, and supplier guidance to reduce risk.

3 hours ago, HennieL said:

Well, that was a long one - but I think this matter warrants some detailed discussions by both "owner/users" and installers.

Being part of a BESS installation in La Réunion island no stone is unturned regarding safety. A company called Akuo Energy was tasked with the building of Lfp battery rooms and enclosures..

Primary focus was on the prevention of a thermal runaway catastrophic event within Lfp battery enclosures. When thermal runaway starts propagating the first line of defence is the detection of Hydrogen gas. The failure progression happens in distinct stages, moving from silent chemical breakdown to catastrophic fire or explosion.

The Pre-Runaway Phase (Off-gassing): As the cell heats up and reaches roughly 150 to 180 deg due to an internal short or abuse the solid electrolyte interphase (SEI) begins to degrade. This breakdown releases Volatile Organic Compounds (VOCs) and hydrogen gas before the full runaway sequence takes over.

To mitigate full blown fire or explosion Hydrogen sensors are used that triggers flame explosion proof extractor fans and AOV's( automatic opening vents)to ensure the Hydrogen and air mixture does not reach critical levels.

For us with small scale lfp installations your best friend would be well ventilated battery areas with moderate charge and discharge curves. Hydrogen sensors could be fitted as a early warning but that would be an expensive exercise. I will do the research and see what i can find in South Africa in the form of pure diatomic hydrogen gas warning systems.

3 hours ago, TaliaB said:

For us with small scale lfp installations your best friend would be well ventilated battery areas with moderate charge and discharge curves. Hydrogen sensors could be fitted as a early warning but that would be an expensive exercise. I will do the research and see what i can find in South Africa in the form of pure diatomic hydrogen gas warning systems.

@TaliaB Thanks - that would be great.

Regarding small-scale protection where batteries are installed in a garage or similar "non-residential part of the house" as in my case, I've been thinking about the advantages and disadvantages of having a "tight fitting" enclosure (with say 30mm-50mm air space between the batteries and the inside of the "wall" of the enclosure) erected around the batteries. My thinking is to use something like compressed rockwool sheets of say 50mm thickness (100kg/m3 density), sandwiched between either (say) 10mm thickness fiber-cement Drywall sheets, or 0.7mm Steel or Aluminium sheeting. The rockwool can withstand +1000 degree Celsius and the Drywall is also A1 fire rated (non-combustible). One could then install some ventilation holes at floor level, and use something like a fireplace chimney installed from this enclosure through the ceiling and then through the exterior wall of the house to allow for continuous passive extraction of any hydrogen and/or nasty vapours from within this enclosure. If thought necessary, one could also install a small blower fan at floor level to blow air through this enclosure + chimney to actively assist with extraction (although I don't think that this would be necessary as hydrogen gas will automatically flow upward, and hot vapour will also rise naturally).

This could (don't know for sure...) have the following advantages:

• Prevent hydrogen explosion by passively and continuously venting the enclosure to the outside of the house.

• Allowing a safe venting path for any toxic chemicals released during a thermal runaway event. This is actually my main concern, as such an event could happen at night while everyone is asleep, and could be overcome by toxic fumes before even realizing that something bad was happening...

• Contain any fire for a time, allowing for other emergency measures (such as waiting for the fire brigade to arrive, which unfortunately is not a given in South Africa any more...)

• Protect the batteries from accidental damage, and also insulate the batteries against cold and hot temperature extremes.

Disadvantages would be:

• Construction cost (although this could be done relatively cheaply by any DIY capable home owner himself. I estimate the cost of the materials would be not more than ~R3000.00 - R5000.00, depending on size and complexity of the extraction system.

• The enclosure would occupy additional space.

• I don't know if it will work, and it will be difficult, if not impossible, to test.

I would really appreciate any feedback and/or thoughts on this. Any fire engineers on this Forum?