Devices powered by lithium-ion batteries are experiencing a notable increase in overheating incidents during airline flights, with a reported 28% rise from 2019 to 2023, according to a report released Monday by UL Standards & Engagement. Although these incidents remain relatively rare, the report highlights a growing safety concern, particularly regarding the placement of such devices in checked baggage.
E-cigarettes were identified as the most frequent offenders among lithium-ion battery-powered devices, with overheating incidents commonly occurring near the seat of the passenger carrying the device. The report notes that in 60% of cases, overheating—known as thermal runaway—happened in the immediate vicinity of the passenger.
Several high-profile incidents underscore the risks associated with lithium-ion batteries. In July, a laptop that began smoking in a passenger’s bag led to the evacuation of a plane at San Francisco International Airport. Additionally, a flight from Dallas to Orlando had to make an emergency landing in Jacksonville, Florida, last year due to a battery fire in an overhead bin.
The report also reveals that more than one-quarter of passengers admitted to placing vaping devices and portable chargers in their checked luggage, despite federal regulations prohibiting such actions. The Transportation Security Administration (TSA) mandates that e-cigarettes, chargers, and power banks with lithium-ion batteries be carried only in hand luggage. This rule is in place because fires in the cargo hold are harder to detect and extinguish.
The data, collected from 35 passenger and cargo airlines—including nine of the ten largest U.S. carriers—shows a troubling trend. The Federal Aviation Administration (FAA) has recorded 37 thermal-runaway incidents this year through August 15, a sharp increase from the 77 incidents reported in 2023, marking a 71% rise from 2019.
Despite the frequency of these incidents, the overall rate remains low given that airlines operate approximately 180,000 flights weekly. However, David Wroth of UL Standards & Engagement emphasizes the unique risks posed by these incidents at high altitudes, stating, “One of these thermal-runaway incidents at 40,000 feet does present unique risks.”
The dangers of lithium-ion batteries in aviation have been known for some time. Following crashes involving cargo planes carrying lithium-ion batteries in 2010 and 2011, the United Nations’ aviation organization considered imposing stricter regulations on such shipments but ultimately decided against tougher standards. Some airlines have since opted not to accept bulk shipments of lithium batteries.
Among the most common lithium-ion-powered devices found on planes are phones, laptops, wireless headphones, and tablets. The report indicates that e-cigarettes account for approximately 35% of reported overheating incidents, while power banks are involved in 16% of cases.