Sounding the Alarm Part 1: UL Solutions on Lithium Battery Risks

Lithium battery incidents involving smoke, fire or extreme heat continue to increase on civil aviation aircraft across the globe.

This 1 June, FAA’s website indicated there were 22 year-to-date incidents in this category through this 23 May. Another 11 incidents were under investigation. This latest activity continues an upward trend from the beginning of this decade of these occurrences.

The surge in lithium battery incidents also has EASA’s laser-like attention. John Franklin, Lead Specialist for Communications and Safety Promotion at the agency, responded to a recent query from this author on the topic, by calling attention to EASA’s Safety Information Bulletin of this 28 May which highlights in much greater detail the risks to safe air travel which can be posed by lithium batteries.

Diverse developments are occurring across the civil aviation enterprise to educate and inform passengers and the wider industry about this safety threat. Of particular interest to CAT followers and readers, there is an “all hands” effort at a number of airlines, in the simulation and training industry and among other stakeholders to defeat this risk.

This is the first of two articles on the risks of lithium battery fires on civil aviation sector aircraft.

In this initial report, we’ll gain brief, but wide-ranging insights and background on the topic from Mike Slowinske, Director of the Principal Engineering Team for Energy and Industrial Automation, at UL Solutions. The organization is a valuable and often unheralded community stakeholder in this safety focus.

In a companion article to be posted tomorrow 11 June, we’ll take a deeper dive into representative training activities designed to help extinguish this safety threat.

UL Solutions as an Active Stakeholder in Eliminating Risk

Mike Slowinske, Director of the Principal Engineering Team for Energy and Industrial Automation, at UL Solutions, spoke with the author this 29 May and provided vital information about his team’s portfolio consisting of batteries, battery chargers, fire protection systems and other materiel relevant to lithium battery safety onboard civil aviation aircraft.

“The mission of UL Solutions is working for a safer world. We exist to perform testing and certification to ensure products meet safety standards. Batteries are a growing concern,” the senior engineer initially said and noted the increase in lithium battery fires in civil aviation and adjacent industries generated UL Standards & Engagement’s 2024 study on Lithium-Ion Battery Safety.

The Northbrook, Illinois-based director recalled the report noted, in part, the incidents of battery fires on board aircraft are increasing. “One reason for that is the number of devices that have batteries. People go onto a plane with on average four, battery-powered devices – your phone, tablet, headphones and a growing concern, e-cigarettes.”

Beyond the surge in battery-powered devices on aircraft, Slowinske emphasized the divergence of whether these devices are or are not certified. The director pointed out laptops and some of the other more “traditional” devices typically come with certification. But, “some back-up battery packs, e-cigarettes and headphones may or may not be certified by a testing laboratory and certification body. That is a concern because you don’t know if an uncertified product has had any testing performed on it.” And here’s the departure point for tested and certified products in this space – as UL Solutions tests to standards that include scenarios for drop, crush and high and low altitude. “If we anticipate the item will be on an airplane, we expect it will be exposed to lower air pressure, and other conditions on a plane – anticipating they will be dropped at some point and ensuring the battery will be safe afterwards. With an uncertified battery, you really don’t know what the condition of the battery will be after it is exposed to those conditions.”

While the UL Solutions engineering lead emphasized uncertified batteries could be a risk anywhere, he also noted there are increased risks on the aircraft from a device being dropped between seats and inadvertently being damaged when seats are adjusted and in other circumstances. In a nod toward the aviation enterprise’s awareness and preventive efforts to counter lithium battery fires, Slowinske recalled his recent travel experiences during which time flight attendants asked passengers to notify the crew to retrieve dropped and hard-to-get phones, and not to do so themselves. “The crews are trained how to safely extract a phone or another device down inside the seat or another area where might be damaged,” he emphasized

Beyond device and battery damage from being dropped is the hazard of changing air pressure. “If you have an aging battery or battery pack, there could be cumulative damage to the components over time. When you bring that into a low air pressure environment, the pressure changes can make that existing damage, which may be very small, into a bigger problem very quickly,” the UL Solutions lead engineer explained and continued, “Maybe if you stayed on the ground the battery might be unaffected for months or years. But with pressure changes – up and down, up and down – you accelerate the battery’s deterioration.”

Slowinske matter-of-factly added many products entering the certification process are designed very safely. “We have products submitted to UL Solutions that pass all of our tests, and they are going to be fine in these environments. It’s the uncertified products that are going to pose an extra risk.”

And how might the broad civil aviation enterprise move forward with batteries and other materiel that do not conform to standards and continue to find their way onto commercial flights? In part, UL Solutions indicated it has a vigorous outreach and engagement strategy with the industry – participating in conferences and other activities to educate stakeholders. “That may be in the battery industry at battery manufacturer conferences, building infrastructure conferences or aviation conferences. We try to attend when and where we can, to educate individuals about what we are doing to keep UL standards up to date, and write new requirements to address new hazards as we find more about the technology. We work with manufacturers on their new inventions and we make sure those are brought to market safely by testing and certifying them according to standards that we try to keep up to date.”

New UL5800 Standard for Containers

UL Standards and Engagement has recently introduced UL 5800 as a standard which is for containers designed to limit a small battery fire. This effort was in response to civil aviation industry’s requests to help crews contain airborne fires with the limited resources at their disposal. The lead engineer added, “UL 5800 could be for a box or a bag designed to contain a fire from a small, rechargeable battery.”

A Nod to Training

Slowinske further called attention to the previously cited Standards and Engagement study which stated the airlines are increasing flight crew training on this safety threat and how to respond to this class of fire. “A very high percentage of flight crew members interviewed for the study said they had been trained on how to respond to these types of fires. I do think the airlines are taking steps to train their crews and raise their awareness.”

Standard Eyed for Cargo Compartments

Of additional interest to CAT followers in the commercial air cargo space, UL Solutions is eyeing a standard for fire suppression systems for cargo compartments. “Knowing this is another industry concern and the frequency of these types of incidents is increasing, our efforts are in response to requests to address this hazard,” the community engineering leader pointed out.

Beyond the recent UL 5800 standard and the evolving standard for air cargo compartments, Slowinske expects to see more lithium battery manufacturers obtaining certification. And highlighting the collaboration occurring in this challenging safety sector, the UL Solutions engineering leader emphasized his organization’s expanding dialogue to gain new ideas, best practices and other insights from battery manufacturers and other community stakeholders.

For a closer look at how airlines and trainers are tackling lithium battery fire threats, read Part 2 now.