Lithium-ion batteries (LIBs) are all the rage these days. They are found in countless consumer devices and range in size from tiny ones found in cell phones to thousand-pound versions in electric vehicles and massive grid-scale Battery Energy Storage Systems (BESS). LIBs are highly efficient and are becoming increasingly cost-competitive with cheaper lead-acid batteries.
The problem is that while lead-acid batteries can also catch fire, a fire in a LIB spreads quickly and is far more dangerous.
Testifying on February 15, 2024, before the U.S. House Of Representatives Committee on Homeland Security, Subcommittee On Emergency Management & Technology, Dr. Lori Moore-Merrell, U.S. Fire Administrator in the Federal Emergency Management Agency, explained:
“These [LIB] batteries are changing the fire risk environment. In a “traditional” fire, it typically takes about three minutes or more for a room to be engulfed but now—with the increased prevalence of LI-ion batteries—there is often only 15 seconds from the first sign of smoke to thermal runaway and explosion, with windows being blown out and fire burning in homes, apartments, and businesses.
“These rapid changes in fire dynamics lead to shorter escape times, shorter time to collapse, and other new and unknown hazards for everyday consumers and for firefighters. Li-ion batteries also present unusual response challenges. While Li-ion batteries are engineered to be safe, the nature of these devices means they may continue to hold a charge after being damaged, even if fully submerged in water.”
Expanding on Dr. Moore-Merrell’s testimony at the hearing was Chief Fire Marshal Daniel Flynn of the Fire Department of New York City, who revealed the magnitude of the problem:
“In 2023, New York City experienced 268 fires caused by these batteries in e-bikes, e-scooters, and other micromobility devices. As a result, 150 people were injured and 18 people were killed. These staggering numbers reflect a crisis that has ballooned over a very short period.
“Additionally, lithium-ion battery fires require large volumes of water to suppress and can reignite spontaneously, making them extremely difficult for firefighters to extinguish. They also pose uniquely grave dangers for the first responders who respond to these fires and risk their lives every day to protect life and property. One example of the detrimental results of these fires occurred last November, killing three generations of a family in one fire. 81-year-old Albertha West, her son, 58-year-old Michael West, and her grandson, 33-year-old Jamil West perished in that deadly fire because an e-bike containing an uncertified lithium-ion battery erupted in flames.
“Unfortunately, these fires continue to plague our city and nation. In my nearly 20-year career, I would be hard-pressed to identify another instance in which a new cause of fires originated and, in only a few years, became one of the leading causes of fatal fires.”
Similarly, testifying in the same hearing, engineer Dr. Stephen Kerber of the Fire Safety Research Institute, UL Research Institutes, Columbia, Maryland, told the committee:
“Despite ongoing safety improvements such as smoke alarms and sprinklers, fires involving lithium-ion battery-powered products are increasing at an alarming rate and have resulted in injuries, fatalities, and property loss. Even when the initial cause of a fire is not the lithium-ion device, the involvement of lithium-ion batteries can increase the intensity and magnitude of any incident.”
Given the concerns of these experts, it is understandable that citizens in the villages of Fitzroy Harbour and Galetta in Ottawa, Canada, are worried about the possibility of battery fires if the $650 million ($500 million USD) 250-megawatt MW BESS planned for only 3 kilometers away is actually built. Their fears were compounded when, according to the Alliance to Protect West Carleton, in the November 1, 2023 public meeting, Evolugen, the proposers of the project, had to be “pressed with questions about the safety of LFP (lithium iron phosphate batteries, the type of lithium-ion battery that Evolugen appeared to be leaning towards)” before they admitted the “risk of fire, albeit rare, would be greater ‘if proper protocols were not followed.’” The alliance states, “The answers provided by Evolugen were often vague and lacking in detail, amplifying the level of mistrust. Our legitimate concerns remain unaddressed.”
Citizens’ confidence in the safety of the BESS project was further shaken when, during the November 29, 2023 Evolugen YouTube public presentation, their safety expert, Devin Keber, FlexGen vice president of safety and compliance, asserted that he was not not aware of any lithium iron phosphate type battery fires.
But anyone can find examples of LFP battery fires on the Web.
It is generally assumed in the industry, and indeed Evolugen implies this, that LFP batteries have greater fire safety than the earlier Lithium Nickel Magnesium Cobalt (NMC) Oxide and other batteries. But is this really true?
Patrick Durham, the Captain and Training Officer at Station 4 in the Troy Fire Department in Michigan, doesn’t seem to think so. Captain Durham, a skilled mechanical engineer who has worked in the fire service since 2006, has been involved in designing innovative multi-material battery structures for electric vehicles. In his YouTube training video, he explains, concerning LFP batteries, that, yes, they can fail catastrophically but most lithium-ion batteries generally start failing around 300° F, while LFP batteries fail around 400 to 500°. So, it appears on the surface that they are less likely to go into thermal runaway.
Captain Durham explains that the problem is the constituents of the gasses produced when LFP batteries burn. When older batteries like Lithium Nickel Cobalt oxide fail, the primary gases given off are indicated in the first pie chart below. Note that 28.7% is hydrogen, which is, of course, highly flammable. When LFP batteries fail, almost half of all the outgases are hydrogen, massively increasing the fire risk.
Another statistic worth considering is burning velocity. While NCA battery chemistry burns at 51 cm/second, LFP burns much more energetically, at 112 cm per second, 120% faster than older battery chemistries. In fact, this is very close to the speed at which highly flammable acetylene burns. And, as I explained in my September 23 America Out Loud article, “The terrifying possibility of thermal runaway in Battery Energy Storage Systems,” a severe fire in an LFP battery could lead to explosions and the release of deadly hydrogen fluoride and other poisonous gases that would quickly kill anyone in contact.
Much of Captain Durham’s conclusions are backed up by recent research led by Dr. Peter J. Bugryniec, one of the world’s leading authorities on the safety of lithium-ion batteries. His research investigates the hazard of thermal runaway with the aim of determining the governing processes and influencing factors that affect thermal runaway severity. The recent groundbreaking scientific research paper, “Review of Gas Emissions from Lithium-Ion Battery Thermal Runaway Failure – Considering Toxic and Flammable Compounds,“ authored by Bugryniec and five professors from three different UK universities, was the first to do a deep dive analysis into the 60 previous scientific studies on gas emissions from lithium-ion battery thermal runaway failure. Among the conclusions listed in the abstract of the paper are:
- “LFP batteries show greater toxicity than NMC batteries,”
- “LFP is more toxic at a lower SOC [state of charge,] while NMC is more toxic at higher SOC (respective to themselves)”
- “LFP off-gas has a greater flammability hazard.”
Dr. Lori Moore-Merrell concluded her February testimony:
“Although research is being conducted to better understand hazards associated with Li-ion batteries and means for mitigation, more research is needed to understand the new and complex hazards Li-ion batteries can present (including exposure to toxic chemicals these batteries release), and to provide firefighters with data and information to inform operational procedures.”
Until that research is completed and LFP Lithium-ion batteries are demonstrated to be truly safe, the Alliance to Protect West Carleton and their councilor, Clarke Kelly (Ward 5 | West Carleton-March [Ottawa]), are justified to oppose the project. Councillor Kelly summed up the situation perfectly on his website:
“With new technology and the associated risk that has been identified, I believe that the scale of this proposal, without assurances of safety, with many details still unknown, is prohibitive to getting the much-needed support of the community.”
Check out our interview with the Alliance’s Monika Miller about their work to block one of the world’s largest BESS systems.
Image: Global News Video
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