Battery fires linked to cellphones, laptops and other electronic devices aboard aircraft have risen 28 per cent from 2019 to 2023, according to a new report, putting passengers at risk and sounding an alarm on a technology vital to the shift toward sustainability.

An analysis by the safety nonprofit UL Standards & Engagement found an average of two lithium-ion battery fires per an approximate 180,000 flights every week in U.S. airspace. The batteries enter into “thermal runaway” - an overheating condition which poses the threats of rapidly spreading fire and possibly even the ejection of shrapnel.

Additionally, incidents per 100,000 passenger departures rose approximately 65 per cent from 2019 to 2023.

The data is based on UL’s Thermal Runaway Incident Program (TRIP), a voluntary lithium-ion battery incident reporting system involving 35 passenger and cargo airlines.

“Passengers are often unaware that many devices they bring on board are powered by lithium-ion batteries, let alone the risks they carry, and it’s much harder to solve a problem that they do not know exists,” David Wroth, director of technology and systems at UL Standards & Engagement, said in a release.

“Thermal runaway incidents on board aircraft are largely preventable, but admittedly more difficult to contend with at 40,000 feet."

The trend is continued north of the border as battery fires from Canadian flights make headlines, and blazes from batteries in electric vehicles and energy storage systems raise concerns.

Thermal runaway incident stats

A majority of airline passengers, 96 per cent, carry at least one device powered by a lithium-ion battery, according to a survey by UL. Smartphones were the most common (82 per cent), followed by laptops (41 per cent), wireless headphones (39 per cent) and tablets (36 per cent).

From 115 thermal incidents in 2023, TRIP data shows a disproportionate amount were caused by e-cigarettes – responsible for 35 per cent of the incidents. Power banks and cellphones tied for second place at 16 per cent each, with laptops in third place at 13 per cent.

Most thermal runaway events happened on the aircraft (87 per cent) in 2023; the remainder involving checked baggage and items which were being carried by passengers (not onboard the aircraft).

Fires and explosions were rare in a thermal runaway at a combined 15 per cent in 2023. Smoke incidents were more common at 38 per cent. The remaining 47 per cent resulted in heat.

Canada’s battery fire risks

Aware of the risk, Transport Canada issued an advisory document and a Civil Aviation Safety Alert this year to raise awareness about the perils of lithium-ion batteries on flights.

But the greatest danger may come on the ground. With the push for more renewable energy and electric vehicles, demand for batteries of all sizes has skyrocketed. That brings with it the potential for dangers similar to those raised by UL.

Lithium-ion battery fires nearly doubled from 2022 to 2023 in Toronto, according to the city's fire service, going from 29 to 51 incidents.

Half of the fire deaths in Vancouver were linked to rechargeable batteries in 2022.

The Canadian Association of Fire Chiefs warned the public about battery fires, which tend to be more intense than typical blazes because of the battery chemistry. Ken McMullen, president of the Canadian Association of Fire Chiefs, noted the increase in battery fires caused by e-bikes and e-scooters.

Battery energy storage projects in Canada and the U.S. have faced opposition from locals due to worries of fires.

The risks of battery fires has led to research into potential solutions and mitigation measures. Companies like Quebec’s EVLO have prioritized fire safety for their battery products. Full Circle Lithium Corp., based in Toronto, has developed a fire extinguisher designed for battery fires.