Japan Bans Power Bank Use on Flights, Limits Passengers to Two Portable Chargers

New Battery Rules Take Effect Across Japan's Flights

Japan's ban on using portable power banks aboard aircraft took effect on April 24, 2026, bringing new restrictions for passengers who rely on spare batteries to keep phones, tablets and other devices running during a flight. Each traveler is limited to two power banks, with a maximum capacity of 160 watt hours per device.

The Ministry of Land, Infrastructure, Transport and Tourism announced the changes on April 14, leaving ten days before implementation. The rules prohibit both directions of charging: passengers cannot use a power bank to recharge another device, and they cannot recharge the power bank itself through an aircraft's seat outlet or USB port.

The policy covers commercial flights operating within Japanese airspace, including flights arriving at and departing from Japanese airports. International passengers connecting through hubs such as Tokyo Haneda and Narita are also affected. The restrictions place Japan among the countries with the strictest controls on portable batteries during air travel.

Violations can carry penalties of up to two years in prison or a fine of one million yen, approximately $6,300. Power banks must remain in cabin baggage, where an overheating device can be noticed and reached, rather than in checked luggage.

For passengers, the immediate change is straightforward: carrying an eligible power bank is still permitted, but using it aboard the aircraft is prohibited. Travelers who previously depended on portable chargers during business trips, long flights or connections now need to charge their devices before boarding and conserve battery power during the journey.

What Passengers Can Carry and Where to Keep It

Japan's new rules combine a limit on quantity with a limit on energy capacity. A passenger may carry no more than two power banks, and neither may exceed 160 watt hours. Bringing several small chargers is therefore restricted even when each individual battery falls comfortably below the capacity ceiling.

Japan Airlines reminds passengers that power banks must never go into checked baggage. Its guidance also advises against placing them in overhead compartments, recommending a seat pocket or a bag under the seat instead. Keeping a battery within reach helps passengers and cabin crew identify and respond quickly if it becomes hot, releases smoke or catches fire.

The prohibition applies whether a power bank is charging a smartphone, a tablet or another electronic device. Plugging the power bank into the aircraft to replenish its own battery is also barred. Passengers need to separate those two activities from simply carrying a charger that meets the baggage rules.

Travelers carrying spare batteries with large capacities for professional camera equipment or medical devices should consult their airline before departure. Additional restrictions may apply, and the rules for a particular battery or medical device need to be checked with the carrier responsible for the flight.

Why Battery Fires Prompted the Change

Japan's National Institute of Technology and Evaluation recorded 123 accidents involving mobile batteries in 2024, a 160 percent increase since 2020. Those accidents ranged from devices emitting smoke to fires or explosions caused by thermal runaway.

Lithium ion batteries power many everyday devices, including smartphones and handheld gaming systems. They are generally safe under normal conditions, but damage, overheating or manufacturing faults can make them unstable. A portable charger puts another such battery into a passenger's bag, separate from the batteries already inside the devices it charges.

Thermal runaway happens when a battery generates heat faster than it can release it. As the temperature rises, reactions inside the battery create still more heat. That process can accelerate without control, releasing flammable gases and producing extreme temperatures, fire or an explosion.

An aircraft cabin makes a battery emergency especially difficult because passengers and crew are inside a confined space. A device that is visible and accessible can be dealt with more quickly than one hidden inside an overhead bag. This explains why the new restrictions address storage as well as charging.

The Japanese accident figures sit alongside a wider aviation safety concern. The United States Federal Aviation Administration has recorded 717 lithium battery incidents aboard aircraft since 2006. It recorded 97 events in 2025 alone, a 93 percent increase over the figure for 2014. Nearly 40 percent of the recorded incidents involved portable battery packs specifically.

Aircraft Fires Added Urgency to the Review

An Air Busan aircraft was destroyed by fire on the ground in South Korea in January 2025. A power bank was suspected as the source of the blaze. The incident helped drive a review of portable battery rules across Asia and was followed by restrictions affecting major South Korean carriers.

Another incident occurred in February 2026, when a Lufthansa flight traveling from Munich to Los Angeles diverted to Salt Lake City after a passenger's portable charger overheated and ignited. Together, the two events illustrated the danger both before takeoff and while an aircraft is in flight.

The main developments leading to Japan's restrictions unfolded over more than a year:

• January 2025: Fire destroyed an Air Busan aircraft on the ground in South Korea, with a power bank suspected as the source.
• February 2026: A Lufthansa flight from Munich to Los Angeles diverted to Salt Lake City after a portable charger overheated and caught fire.
• March 2026: The International Civil Aviation Organization revised its dangerous goods rules to address portable charger risks.
• April 14, 2026: Japan's transport ministry announced its new power bank restrictions.
• April 24, 2026: Japan's ban on using and charging power banks aboard aircraft took effect.

Japan's policy addresses several parts of the same risk: fewer spare batteries per passenger, a ceiling on their capacity, no charging activity during flight and storage that allows a problem to be spotted promptly.

International Rules Are Moving in the Same Direction

The International Civil Aviation Organization, the United Nations specialized agency that sets aviation standards for 193 member countries, adopted revised dangerous goods guidelines in March 2026. Japan's changes follow that international response to the growing fire risk from portable chargers.

South Korea introduced similar restrictions across major airlines, including Korean Air and Asiana Airlines, following the Air Busan fire. In Taiwan, EVA Air and China Airlines have prohibited both using power banks and charging them during flight.

Thai Airways, Singapore Airlines and Malaysia Airlines have introduced comparable prohibitions. Hong Kong's Civil Aviation Department imposed immediate restrictions limiting departing passengers to two power banks and prohibiting charging during flight. Cathay Pacific Airways applied those measures across its entire network.

Lufthansa became the first major European Union airline to ban power bank use on flights. It allows exceptions for approved medical devices, making advance confirmation with the airline particularly relevant for passengers who need battery power for medical equipment.

The common direction is toward tighter controls, but the details vary by airline and jurisdiction. Some policies focus on whether a power bank can be used, while others also set different limits on the number of batteries or specify where passengers must keep them.

American Airlines Have Their Own Limits

Southwest Airlines limits passengers to one power bank, which must remain within reach instead of being stored in an overhead bin. That allowance is smaller than Japan's limit of two devices per person.

American Airlines is scheduled to reduce its allowance from four power banks to two beginning in May 2026. As of April 30, that change is still ahead. It will halve the carrier's permitted number of devices, bringing the quantity limit into line with Japan's new allowance.

Delta and United have also introduced limits of two devices, with storage requirements that keep the batteries within passengers' sightlines. Across these policies, the location of a battery matters alongside its size and the number being carried.

Most major airlines are bringing their policies closer together, but passengers with connecting itineraries still need to check each flight. A battery permitted on one carrier may face a tighter quantity limit, different storage instructions or a ban on use on the next segment.

How to Read a Power Bank's Capacity

The 160 watt hour ceiling measures the amount of energy a battery can store. Many power banks display their capacity in milliampere hours instead, so passengers may need to check more than the large number printed on the packaging.

Watt hours are calculated by multiplying the battery's rated capacity in ampere hours by its rated voltage. When capacity is given in milliampere hours, the calculation is: milliampere hours multiplied by rated voltage, divided by 1,000.

Standard power banks for smartphones typically range from 10,000 to 30,000 milliampere hours, or roughly 37 to 111 watt hours. Those common sizes fall below Japan's 160 watt hour maximum. Larger power banks intended to charge laptops may exceed it.

Passengers should look for the watt hour rating printed on the device or use its stated capacity and voltage to calculate the figure. Security personnel may refuse a battery without visible specifications because its capacity cannot readily be checked.

Japan Airlines has also indicated that International Air Transport Association rules may lower the permitted capacity to 100 watt hours beginning in January 2027. That possible change would matter for batteries near the upper end of the current range: a device rated at 111 watt hours is below 160 watt hours but above 100 watt hours. The lower ceiling remains a possible future change, rather than the limit introduced in Japan on April 24.

Connections Through Tokyo Require Extra Planning

Tokyo Haneda and Narita handle international passengers who may encounter different battery policies over a single journey. Japan's restrictions apply to departures from Japanese airports, including connecting flights, regardless of the airline's nationality.

A traveler flying from New York to Bangkok through Tokyo could be allowed to use a power bank on the first flight by the originating carrier, then be prohibited from using it on the flight departing Tokyo. The charger would need to meet the Japanese carriage limits even though it remained unused on that second leg.

An American airline operating a flight from Tokyo is subject to Japanese regulations for that departure. The same airline's departure from Los Angeles follows Federal Aviation Administration guidelines. Airline policies may also apply across a carrier's network, which is why passengers need to check the rules for every segment rather than relying on the first departure alone.

Business travelers working through long flights, passengers playing handheld games and tourists using phones for entertainment all face the same practical adjustment. Charging devices before boarding and conserving their batteries becomes more important when a portable charger can be carried but cannot be used.

Travelers Weigh Inconvenience Against Safety

At Tokyo Haneda Airport, passengers described the inconvenience of losing access to portable charging during a flight while accepting the safety reason for the restriction. One traveler explained that the experience of battery fires made the new rule understandable.

Being unable to recharge my devices during a flight is inconvenient, but it cannot be helped because fires have occurred.

Another traveler said he had previously relied on mobile batteries during business trips and would now make sure everything was charged before boarding. His adjustment reflects the central change for frequent passengers: preparation before takeoff replaces the option of topping up a device from a power bank during the journey.

A long itinerary can make that preparation more demanding. Passengers may use their phones or tablets during an initial flight and a connection before boarding the next aircraft. Checking the rules for each segment and managing battery use across the whole trip can help avoid being left with an empty device when portable charging is prohibited.

Airports Explain the Rules as Enforcement Begins

Japanese authorities launched public awareness efforts ahead of the April 24 deadline. At Haneda, flight attendants and ground staff from the Scheduled Airlines Association of Japan handed travelers explanatory leaflets, outlined the restrictions and asked for cooperation with the new safety procedures.

Airline check in counters now display prominent notices about portable charger policies. Security screening has been adjusted to identify passengers carrying too many power banks, and airport personnel are authorized to confiscate devices that exceed the limit of two or the maximum capacity of 160 watt hours.

Enforcement can extend beyond removing a battery at the airport. First offenders may receive warnings, while repeated or serious violations can lead to prosecution under Japan's Civil Aeronautics Law. The potential penalties are up to two years in prison or a fine of one million yen, approximately $6,300.

The combination of leaflets, counter notices, screening and legal penalties shows how Japan is implementing the policy: passengers are being told what to bring and how to store it, while authorities have powers to address breaches. For travelers preparing to fly, the essential checks are the number of power banks, their marked capacity, their location in cabin baggage and the ban on using or recharging them aboard the aircraft.

The Essentials

• Japan's power bank restrictions took effect on April 24, 2026, after an announcement on April 14.
• Passengers cannot use power banks to charge devices or recharge power banks through aircraft outlets or USB ports.
• Each passenger may carry two power banks at most, each with a maximum capacity of 160 watt hours.
• Power banks belong in cabin baggage, not checked luggage. Japan Airlines recommends accessible storage in a seat pocket or under the seat rather than an overhead compartment.
• The rules affect flights arriving at and departing from Japan, including international connections through Haneda and Narita.
• Violations can lead to up to two years in prison or a fine of one million yen, approximately $6,300.
• Japan recorded 123 mobile battery accidents in 2024, while the FAA recorded 97 lithium battery incidents aboard aircraft in 2025.
• American Airlines plans to reduce its allowance from four power banks to two in May 2026. Japan Airlines has indicated a possible 100 watt hour ceiling under IATA rules from January 2027.
• Passengers should charge devices before boarding, verify battery specifications and check the policy for every flight in their itinerary.