If you have recently flew, you may have heard that flight attendants say that the output bank can only be used if it is under your constant supervision during pre-made briefings. In fact, Southwest Airlines has announced a new policy that if you use portable chargers on your planes, you will need to stay in front of you. “Don’t charge your overhead bin devices,” warns Southwest. Also, several Asian airlines have implemented similar policies, prohibiting flyers from placing batteries in overhead bins and banning passengers from using portable batteries while flying.
Similarly, if you checked your bag, the agent probably asked if there were any items with a lithium-ion battery that include laptops, phones, tablets, electronic toothbrushes and other rechargeable items.
According to Professor Venkat Viswanathan, an expert on aviation batteries, the problem is that lithium-ion batteries can overheat or short circuit, especially if they are damaged. This can lead to a process known as thermal runaway, leading to smoke, fire and, in some cases, explosions.
“If one of them sets a fire, the entire cargo can get burned very quickly,” Viswanathan said.
Thermal runaway events are rare, but they do happen. For example, in November 2024, my phone started a fire in an airplane shed just before takeoff. Passengers had to evacuate, and two people were injured.
According to the Federal Aviation Administration (FAA), there were 620 verified cases in the United States between March 3, 2006 and April 27, 2025 involving lithium batteries. The most common issues were battery packs (240 incidents), followed by e-cigarettes (131), cell phones (93), other electronic devices (78), laptop computers (75), and medical devices (3).
Except for 2014 and 2020, the number of incidents has risen every year since 2014.
There were 22 incidents between January 1st and May 23rd, 2025 (when the FAA recently updated its online incident report). New FAA data shows that it occurs on an average of two flights each week.
John Cox, CEO of the safety operating system at an aviation consulting firm and former pilot, added that thermal runaways is not ideal for either the cabin or cargo, but flight attendants can respond to the issue more quickly in the cabin once the battery starts smoking or fires.
Cox said he hopes that the number of lithium battery fires on planes and elsewhere will continue to increase, which is due to an increase in lithium batteries in our society.”
To mitigate the risk of these incidents, the FAA encourages flyers to check for device recalls and damages, as they are “highly likely to create sparks or generate dangerous evolutions of heat.”
Passengers can also protect themselves and others by storing electronic devices in sleeves and cases. If the device is squeezed too hard, it can damage the battery. This can cause heat rampage. Avoid slight cushioning from the protective casing. Similarly, if your phone fits between your seats, it’s important not to try and retrieve it yourself. If it gets damaged, the battery can smoke or ignite. Flight attendants are trained to collect phones safely.
Additionally, passengers can prevent the plane from thermal runaway by turning the device completely off when not in use.
If your device overheats, smokes, or catches fire on a mid-flight, contact your crew immediately. It has a fire extinguisher and heat containment bag that helps limit oxygen to the device, prevent the spread of fires and neutralize the danger.
This article was originally published in October 2023 and updated on May 23, 2025, and contains current information.
