Lithium-ion batteries are overheating more frequently during airline flights, with overheating incidents rising 28% from 2019 to 2023, according to a report by UL Standards.

E-cigarettes are the most common device to overheat, with 60% of cases occurring near the passenger’s seat. The Transportation Security Administration prohibits e-cigarettes and chargers with lithium-ion batteries in checked bags but allows them in carry-on bags.

The report found that over one-quarter of passengers surveyed put vaping cigarettes and portable chargers in checked bags, which is against federal rules.

The Federal Aviation Administration reported 37 thermal-runaway incidents on planes this year, a 71% increase over 2019.

The most common lithium-ion-powered devices on planes are phones, laptops, wireless headphones, and tablets.