Power bank on a plane: the rules for carrying and using it safely

In the cabin, not in your suitcase

Before the numbers, the first distinction to make is between carry-on and checked luggage. Power banks and other spare lithium batteries — meaning ones not installed inside a device, like battery cases for smartphones — have to travel in carry-on luggage only: it’s the rule the FAA (the US agency that regulates aviation), the TSA (which enforces it at security checkpoints), IATA (the international association of airlines) and EASA (the European aviation safety agency) all agree on. Devices with a battery already built in (a laptop, a phone, a camera) can in some cases travel in the hold too, but the general recommendation is still to keep them in the cabin.

The reason isn’t bureaucratic box-ticking. If a lithium battery goes into thermal runaway — a chain reaction in which it overheats, releases gas, and can catch fire — the only way to act quickly is to have the device where someone can see it. In the cabin, a crew member can spot the early signs of a fire and respond within seconds; in the hold, sealed inside a suitcase among dozens of others, no one would notice until smoke started showing up somewhere else. That’s also why spare batteries have to stay in the cabin even when switched off: turning a device off doesn’t protect against internal faults in the battery powering it.

Example: a passenger has a power bank in their backpack, and at the boarding door they’re told the bag has to go in the hold because the overhead bin is full. Before handing it over, they need to open the bag and take the power bank out, keeping it with them in the cabin — this is exactly the situation IATA describes for full flights, where the bag itself goes in the hold but spare batteries never do, no matter what.

The terminals of spare batteries also need protection against short-circuits: insulating tape over the contacts, the original packaging, or a separate pouch all work. It’s a small precaution that removes one of the most common ways a battery can start heating up without anyone intending it.

Three brackets, measured in watt-hours

Beyond where you pack it, a power bank’s capacity matters too. The reference measure is the watt-hour (Wh), calculated by multiplying the battery’s rated amp-hours (Ah) by its voltage; by law, the value has to be printed on the casing, which helps anyone holding a power bank that only states milliamp-hours (mAh) rather than Wh directly.

Non-rechargeable lithium metal batteries, like some camera batteries, follow a different scale based on grams of lithium: up to 2 grams with no approval, between 2 and 8 grams only with the airline’s approval and a maximum of two spares. For most batteries there’s no explicit cap on how many you can carry, but they have to be for the passenger’s personal use, and the final call on what clears security still rests with the officer on duty.

These three brackets remain the shared international baseline, not necessarily the last word: many airlines impose stricter limits than the FAA, TSA and IATA minimums, so it’s always worth checking your carrier’s website before flying, especially if you’re traveling with devices that come close to the 100 Wh threshold — a high-end laptop or a very large power bank can sit right near it.

A fire on the ground, and what it changed

On January 28, 2025, an Airbus A321 operated by the South Korean airline Air Busan (Flight 391) caught fire while parked on the ground during taxi, at Gimhae International Airport near Busan. There were 176 people on board, all evacuated; the preliminary investigation recorded seven minor injuries, while the aircraft itself was destroyed by the flames. On March 14, 2025, South Korean authorities attributed the cause to a breakdown in the internal insulation of a power bank stored in the overhead bin, above passengers’ heads, which was said to have triggered a short circuit.

The critical factor wasn’t really the power bank itself but where it was. Stored in the overhead bin, no one could notice what was happening inside it in time — the same principle, flipped around, that underlies the “never in the hold” rule: what matters is that a battery in trouble stays visible and within reach of someone who can act. After the incident, South Korea’s Ministry of Land, Infrastructure and Transport introduced, from March 1, 2025, a ban on storing power banks and e-cigarettes in overhead bins, a ban on charging them through seat-back USB ports, and a limit of five power banks per passenger per flight.

Some airlines went further than their own country’s rules. Air Busan, Korean Air and the other Hanjin Group carriers (Asiana, Jin Air, Air Seoul) banned using power banks in flight starting January 26, 2026: passengers can still bring one, but can’t use it to charge devices, and it has to stay within reach — in a pocket, the seat-back pocket, or under the seat — never in an overhead bin. Singapore Airlines and its low-cost arm Scoot introduced a similar rule from April 1, 2025: no charging power banks through onboard USB ports, and no using a power bank to charge personal devices for the entire flight.

These are rules set by individual airlines, born out of one real incident and a wave of regulatory tightening that started in South Korea, not an IATA or ICAO standard that applies to every flight worldwide: as of this Recap’s writing, IATA flags new power bank rules due to take effect on January 1, 2027, and in the meantime advises passengers to always check their own airline’s current guidance, since it’s subject to revision. It’s the same mindset needed to understand the electric current running through any battery-powered device in the first place: anyone wanting a refresher on where the energy a power bank stores and releases actually comes from can read the Recap on how electric current works.

Not just a question of charge

It’s tempting to assume the risk only applies to batteries that are very full or very old, but the causes of thermal runaway are more varied: EASA, which works alongside IATA and ICAO on these recommendations, cites physical damage (impacts, crushing), overcharging, improper packaging, and counterfeit or low-quality batteries bought from unreliable sellers. Even a power bank that looks perfectly fine, like the one on Air Busan Flight 391, can carry a manufacturing defect in its internal insulation that surfaces without warning.

That’s the basis for a few practical recommendations shared by EASA, IATA and ICAO, useful regardless of any individual airline’s own rules: keep the power bank somewhere you can monitor it, not stashed away and forgotten; avoid charging devices from a power bank in flight and avoid recharging the power bank itself on board; buy batteries from original retailers. They’re the same kind of care that applies to any sensitive piece of electronics — not so far removed from the batteries powering large parts of the transport industry by the mid-2020s, including the struggles the European automotive sector has faced in its own shift to electric vehicles, covered in the Recap on the European automotive industry crisis.

One last parallel is worth drawing about how aviation handles technical risk more broadly: an aircraft’s black box exists for exactly this reason, to reconstruct precisely what happened after an incident — the same principle that let South Korean investigators trace the Flight 391 fire back to a single power bank. Anyone curious about how that kind of reconstruction actually works can read the Recap on the flight data recorder, which covers what it really records and how it’s recovered.