Power banks and lithium batteries on airplanes: watt-hour limits and airline rules

Before a spotting trip, the same things usually lie on the bed: camera, two or three spare batteries, a hefty power bank for your phone and mobile ADS-B reception, maybe a small drone as well. At the latest at the security checkpoint, it becomes clear whether all of it is allowed through. This guide explains the rules for power banks and lithium batteries on airplanes: how to convert mAh to watt-hours, which limits apply at 100 and 160 Wh, what changed in 2026 through ICAO and why some airlines are even stricter.

The short answer

Power banks and loose spare batteries always belong in your carry-on, never in checked baggage. Up to 100 watt-hours per battery you need no approval. Between 100 and 160 Wh the airline must agree, and you may take at most two such spare batteries. Anything over 160 Wh is off limits for passengers. Since March 27, 2026, ICAO rules also limit the number of power banks to two per person and prohibit charging power banks during the flight.

Beyond that, every airline may set its own, stricter rules – and many now do. The basic rules are uniform internationally, the details on board are not.

Why lithium batteries are taken so seriously on board

Lithium-ion cells store a lot of energy in a small space. If a cell is damaged, overcharged or short-circuited, it can heat up so much that it catches fire and takes neighboring cells with it – so-called thermal runaway. In an aircraft cabin, such a fire is manageable because the crew can see and fight it. In the cargo hold or in a closed overhead bin, by contrast, nobody may notice it in time.

That is exactly the reason for the central rule: loose batteries fly in the cabin, where someone can intervene. January 2025 showed how serious the situation can become. On January 28, 2025, a fire broke out on board an Airbus A321 of Air Busan at Gimhae Airport in Busan while the aircraft was preparing for the flight to Hong Kong. All 176 people on board were evacuated via the escape slides, and the aircraft burned out. South Korean investigators later named a power bank in an overhead bin above the seats as the probable cause of the fire.

From mAh to watt-hours: how to calculate

On most power banks the capacity in milliamp-hours is printed large, for example 10,000 or 20,000 mAh. For air travel, however, the stored energy in watt-hours (Wh) counts. The formula is simple:

Wh = mAh × volts ÷ 1,000

What matters is the nominal voltage of the cells, not the output voltage at the USB port. For power banks it is usually 3.6 or 3.7 volts and is printed small on the case. A few examples:

Battery	Capacity	Nominal voltage	Energy	Classification
Small power bank	10,000 mAh	3.7 V	37 Wh	up to 100 Wh, no approval
Large power bank	20,000 mAh	3.7 V	74 Wh	up to 100 Wh, no approval
Very large power bank	26,800 mAh	3.7 V	about 99 Wh	just under 100 Wh
Camera battery (example)	2,000 mAh	7.2 V	14.4 Wh	up to 100 Wh, no approval
Large video battery (example)	10,000 mAh	14.4 V	144 Wh	100–160 Wh, airline must approve

The calculated values are examples – the figure on your battery is always what counts. Many manufacturers now print the Wh figure directly. Then you do not need to calculate at all.

The limits at a glance

The basis is ICAO’s dangerous goods regulations, which the airline association IATA implements in its dangerous goods rules. IATA summarizes them for passengers in a simple overview. A distinction is made between batteries installed in a device and loose spare batteries. Power banks expressly count as spare batteries because their purpose is to supply power to another device.

Energy	Configuration	Carry-on	Checked baggage	Airline approval
up to 100 Wh	in the device (camera, laptop, phone)	yes, up to 15 devices	yes	no
up to 100 Wh	spare battery, power bank	yes, up to 20 spare batteries	no	no
over 100 to 160 Wh	in the device	yes	yes	yes
over 100 to 160 Wh	spare battery, power bank	yes, at most two	no	yes
over 160 Wh	any form	no	no	only as dangerous-goods cargo

Two additions come on top. For non-rechargeable lithium metal batteries, the lithium content applies instead of the Wh figure; the limit without approval is 2 grams. And the maximum numbers of 15 devices and 20 spare batteries can be raised by the airline on request. The batteries must also have been tested to a UN test standard, which is the norm for branded products.

Short-circuit protection: the part many forget

Loose spare batteries must be individually protected against short circuits. IATA names several ways: the original packaging, taped-over contacts, or a separate plastic bag or protective sleeve per battery. With camera batteries, protective caps usually come with the delivery – that is exactly what they are for.

The risk is quite practical: if two batteries with exposed contacts lie in the same pocket among keys, coins or memory cards, a piece of metal can bridge the terminals. That is why:

• Always keep camera batteries with a cap or in a small battery compartment in the camera backpack.
• Transport power banks without a cable plugged in when you are not using them.
• Do not pack damaged, swollen or dropped batteries at all.

How to stow the rest of your photo gear in carry-on is covered in the guide Camera gear in carry-on.

Airline rules: where it gets stricter

The ICAO and IATA rules are the minimum. Airlines and national authorities may go beyond them, and since the Air Busan fire, many have done so, especially in Asia. An overview of documented examples, as of October 2026:

• South Korea: Since March 1, 2025, power banks may no longer go in the overhead bins on flights of South Korean airlines. Charging power banks via the USB ports at the seat was also banned, and there was an upper limit of five power banks per person. This affects, for example, Korean Air, Asiana Airlines and Air Busan.
• Taiwan: EVA Air banned the use of power banks on board from March 1, 2025, and China Airlines also prohibited use in spring 2025.
• Singapore: Singapore Airlines and its low-cost subsidiary Scoot have prohibited both the use and the charging of power banks on board since April 2025.
• China: On domestic flights in China, since June 2025 only power banks with the Chinese mandatory certification CCC (3C marking) are allowed. Before a China domestic flight, check whether your power bank carries this marking.

For Europe: here too, airlines keep adjusting their conditions of carriage, and since March 2026 the new ICAO rules apply to international air travel. Whether you may use the power bank during the flight to charge your phone, whether it may lie in the bin above the seat and how many you may carry is stated in your airline’s dangerous goods notices – whether Lufthansa, Eurowings, Ryanair or Emirates. Read them before every flight, not just once a year.

What this means for your spotter gear

Most spotters manage the basic rules without problems because typical camera batteries are far below 100 Wh. It gets tight in three places.

Power banks: If you used to take three or four power banks, you have to cut down to two since 2026. A sensible setup is one large power bank just under 100 Wh for long days at the fence and a small one for your jacket pocket. More capacity does you little good on board anyway if use is prohibited.

Drone batteries: Many batteries of small camera drones are under 100 Wh, larger models can be above it. Check every battery individually and, for more than 100 Wh, clear the approval with the airline beforehand. How to transport the drone itself safely is in the article Taking a drone on a plane. What you have to observe with the drone on site is explained in the guide Taking the drone on vacation.

Video batteries: Large batteries for video lights or cameras with a battery plate quickly reach 100 to 160 Wh. There are variants that deliberately stay just under 100 Wh – for travel they are the less complicated choice.

Typical pitfalls at the checkpoint and gate

The trolley is checked at the gate. On full flights, airlines often take carry-on bags at the gate and load them into the cargo hold – how that works is shown in The journey of a suitcase. Then the power bank, loose batteries and ideally the camera too have to come out beforehand. Pack them in a small bag you can take out quickly.

The power bank is in the suitcase. If it is discovered when checked baggage is screened, the suitcase is opened or the power bank is removed. At best it costs time, at worst the power bank.

The labeling has rubbed off. Older power banks often lose their rating label. Take a photo of the labeling before the trip while it is still legible, or replace the power bank.

Charging on the plane. Since March 2026, charging power banks on board is off limits under ICAO rules. If you use the seat outlet, then for your phone or camera directly, not for the power bank – and only if the airline allows it.

The battery gets hot. If you notice on board that a battery is getting unusually warm, smoking or deforming, tell the cabin crew immediately. Do not hide it and do not try to extinguish it yourself. The crew is trained and equipped for exactly this case.

General information about the checkpoint itself – for example, why photography is not allowed there – is in the articles Why photography at the security checkpoint is prohibited and Landside, airside, security area.

Planning power for the spotting day

If power banks may no longer be charged on board and in some cases no longer used, planning shifts. If you arrive in the morning and want to go straight to the spot, power bank and batteries should already be full before departure. A few habits help:

On the road, you save battery if you photograph selectively at the window instead of filming continuously – ideas for that are in the guide Photos from the airplane window. What else belongs in the bag is summarized in the Gear checklist.

Conclusion

The rules for power banks and lithium batteries on airplanes follow a clear logic: loose batteries fly in the cabin, where the crew can notice a fire, and the energy in watt-hours determines what is allowed without approval. With the formula mAh times volts divided by 1,000, you can classify any battery yourself. New since 2026 is the upper limit of two power banks per person along with a charging ban on board, and many airlines go even further. If you count before the trip, protect the contacts and read the airline rules, you will reach the fence at your destination airport relaxed.