If you’ve flown recently, you may have heard the flight attendant mention that power banks can only be used if they’re under your constant supervision during the predeparture briefing. In fact, Southwest Airlines just unveiled a new policy that if you use a portable charger in-flight it must remain in plain sight. “Do not charge devices in the overhead bin,” Southwest warns. And several Asian airlines have implemented a similar policy, prohibiting fliers from placing batteries in the overhead bins or banning passengers from using portable batteries at all during the flight.
Similarly, if you’ve checked a bag, the agent probably asked if you had any items with lithium-ion batteries—including laptops, cell phones, tablets, electronic toothbrushes, and other rechargeable items—in your luggage and if you do, that you take them out, as federal rules mandate that they must go in a carry-on bag or be left at home.
The issue is that lithium-ion batteries are capable of overheating or short-circuiting, especially if they are damaged, according to University of Michigan professor Venkat Viswanathan, an expert in batteries for aviation. This, in turn, can lead to a process called thermal runaway, resulting in smoke, fire, and, in some cases, explosions.
“If one of them catches fire, then very quickly, the entire cargo hold could be in flames,” Viswanathan said.
While thermal runaway events are rare, they do happen. In November 2024, for instance, a cell phone caught fire in the cabin of a plane shortly before takeoff. The passengers had to evacuate and two people were injured.
According to the Federal Aviation Administration (FAA), there have been 620 verified incidents in the United States involving lithium batteries between March 3, 2006, and April 27, 2025. Of those, at least 465 incidents happened in the cabin and 129 in the cargo hold (the remaining were not classified). The most common issue involved battery packs (240 incidents), followed by e-cigarettes (131), cellular phones (93), other electronic devices (78), laptop computers (75), and medical devices (3).
The number of incidents has trended upward every year since 2014, with the exception of 2019 and 2020.
Between January 1 and May 23, 2025 (when the FAA most recently updated its online incident report), there were 22 incidents. New FAA data shows it happens on an average of two flights each week.
John Cox, CEO of aviation consulting firm Safety Operating Systems and a former pilot, added that while thermal runaway isn’t ideal in either the cabin or in cargo, if a battery does begin to smoke or catches fire, flight attendants can respond to the issue more quickly in the cabin.
Cox said he expects that the “number of lithium battery fires, on airplanes and elsewhere, will continue to increase. This is due to the increase of lithium batteries in our society.”
To help reduce the risk of these incidents, the FAA encourages fliers to check for recalls or damages to their devices, as they’re more “likely to create sparks or generate a dangerous evolution of heat.”
Passengers can also protect themselves and others by keeping electronics in a sleeve or case. If a device is squeezed too hard, it could damage the battery, which could cause thermal runaway—a little cushion from protective casing helps prevent that from happening. Similarly, if your cell phone falls between the seats, it’s important not to try to retrieve it yourself—if it gets damaged, the battery might smoke or catch fire. Flight attendants are trained to retrieve phones safely.
Furthermore, passengers can prevent thermal runaway on planes by turning devices completely off when not in use.
If your device should overheat, smoke, or ignite midflight, contact a crew member immediately. They have fire extinguishers and thermal containment bags, which restrict oxygen to the device and prevent the spread of fire, to help neutralize the danger.
This article was originally published in October 2023, and was updated on May 23, 2025, to include current information.