Travel salts and make the fast checkeo: molts, clothes, pajamas, jacket in case it refreshes (which you will end up not using), loaders and the power bank of 30,000 mAh with which you can load your mobile and that of all your friends a couple of times. You keep everything, you arrive at the airport and surprise: you can’t pass with such a large external battery, so they requisition and lose it.
Indeed, in the same way that we can only wear liquid boats of up to 100 milliliters in a transparent plastic bag of up to a liter of capacity, external batteries also have limits. Knowing them will help us not to take an unpleasant surprise as soon as you start the holidays
Let’s talk about airplanes. IATA (International Air Transport Association) is the global commercial organization that groups the majority of the world’s airlines. It represents more than 350 airlines in 120 countries (that is, 80% of world air traffic) and among its many tasks is the promotion of safety standards. It is in the 66th edition of the IATA Dangerous Goods Regulations where the limits of lithium and ion-lithium batteries (PDF) are collected.
Image | WorldOfSoftware
The limits. According to the IATA, we can carry in the hand luggage, and always in the hand luggage, not in the winery, a maximum two external batteries of up to 100 Whing each. The same is secreted by EASA (European Aviation Safety Agency) (PDF). IATA terminology, however, is something confusing because it considers the Power Banks as spare/loose batteries, and of those we can take up to 20.
However, if they are non -spillable batteries, they must be 12V or less, 100 whi or less and the limit is two units per person. If it is a replacement battery of between 100 and 160 WH, we can take up to two that the operator approves it and if it is greater than 160 WH, we most likely cannot transport it, as the EASA exposes. So, and to go on insurance:
- Maximum capacity: 100 Wh
- Maximum units per person: two Power Banks.
Imagen | Gomi
Forgive, ¿WH? In the Tech world we are accustomed to talking about the ability of a battery in terms of MAH (Milliampress hour), but IATA tells us about Wh (watts time). If the brand of our Power Bank gives us the data, better than better. If not, we can do the MAH> WH conversion with this formula:
(mAh) X (V) / 1000 = Wh
Power Bank usually have a 3.7 volt voltage, so in the case of an external 20,000 mAh battery we would be talking about 74 Wh. That leads us to the following conclusion: if we want to carry the Power Bank on an airplane, the maximum theoretical capacity must be, at most, 27,000 mAh, although it may be tightening the rope too much. With a battery of 20-25,000 mAh we should go more than served, so, again, to go on insurance on an plane:
- Maximum capacity: 20,000-25,000 mAh.
- Maximum units per person: two Power Banks.
Imagen | Gomi
But one thing. This is a general rule and airlines usually accept it or adapt it, but we have doubts the ideal is to speak with the operator and comment our particular case. It is also possible that there are concrete norms depending on the country or the airline.
For example, Hong Kong’s laws prohibit loading the Power Banks using the USB take of the seats or loading devices with the external battery during the flight. South Korean operators force the battery at all times with us (not in a backpack, not in the upper trunk, with us) and companies such as China Airlines and Singapore Airlines prohibit their use during the flight.
China’s case is particular. The Civil Aviation Administration of China (CAAC) issued an urgent notice by which, as of June 28, 2025, passengers are prohibited from climbing to the plane with batteries without the 3C certification (CCC). This is a mandatory security brand, similar to the European EC, which guarantees the quality and safety of Chinese products and that applies to both those imported and those manufactured in China. The thing is that, for the moment, it only applies to domestic flights.
And in the trains? Neither in the conditions of Renfe nor on the Adif website any mention is made to external batteries. Renfe, in fact, considers dangerous objects to firearms, white weapons, sports and sharp work instruments. Weapons could behave if we carry the relevant license or accreditations, as well as ammunition.
What we cannot carry are sharp objects such as knives or stabs, paint ball guns and explosive, flammable, chemical or toxic substances. They do not specify anything about external batteries. Nor do Iro and Ouigo, which have similar restrictions and in any case refer to external batteries. Anyway, from WorldOfSoftware we have contacted the three operators to get out of doubt and update in the case of receiving an answer.
Image | Tonny Zhong
