Heading out for summer trips soon? If you intend to pack an extra battery charger for your phone or gadgets, stay up to date on current regulations for air travel.

Rechargeable lithium-ion portable battery chargers, commonly called power banks, come in protective cases of many shapes and sizes. They offer a convenient method to add power while traveling.

Following several smoke or fire events, U.S. and global aviation bodies have released fresh recommendations, and carriers have updated their policies for passengers.

Here is what you need to know about traveling with power banks.

The key rule is that lithium battery chargers cannot go in checked bags. They must stay in carry-on luggage instead.

Passengers may usually carry two lithium-ion power banks rated up to 100 watt hours without prior airline permission. This amount suffices to recharge a cellphone multiple times.

For non-rechargeable lithium metal batteries, the cap is two grams of lithium content per unit. Standard AA and AAA cells hold under one gram of lithium.

These thresholds include most lithium batteries found in typical personal electronics, per the Federal Aviation Administration.

The FAA notes that newer lithium-ion batteries often display a watt-hour rating on a label. If capacity appears in milliampere hours, convert the value using math or the FAA online tool.

Calculate watt hours by dividing the mAH figure by 1,000 to reach ampere hours, then multiply by the usual 3.7 volts. A 10,000 mAH unit equals 10 ampere hours, yielding 37 watt hours after multiplication.

Airline approval is required for larger lithium-ion batteries rated 100 to 160 watt hours, often found in professional video or medical devices.

Carriers treat lithium battery fire risks seriously after multiple recent events.

A major case occurred in January 2025 when fire erupted on an Air Busan aircraft at a South Korean airport, leading to full evacuation of 176 passengers.

The FAA has recorded nine lithium battery incidents this year, with six involving power banks.

Battery concerns have caused flight disruptions even without active issues. Last month an Easyjet service from Egypt to Britain diverted to Rome after a passenger reported a power bank charging a device in checked luggage.

Lithium batteries in cargo holds create hazards because crews cannot quickly reach and control any smoke or fire, according to the International Air Transport Association.

Storing them in the cabin allows faster response using fire-resistant bags and gloves to manage overheating units.

The chance of a lithium-ion battery short-circuiting remains low, yet any resulting fire can prove severe, noted Paul Christensen, a professor of electrochemistry at the University of Newcastle.

Lithium batteries pack substantial energy in limited space, Christensen explained. Problems arise from crushing, overcharging, or overheating, which may start thermal runaway producing heat and harmful gases.

Christensen suggests inspecting power banks for damage. Bulging or excessive heat during charging may indicate faults.

He also warns against low-cost units from unknown makers that may lack quality controls. Poorly made batteries can trigger thermal runaway long after purchase.

Once aboard, airlines enforce strict handling rules for power banks.

They cannot go in overhead bins. Keep them accessible, such as in the seatback pocket or under the seat ahead.

Avoid using them to charge devices mid-flight or recharging via plane power outlets.

If a battery or device falls beside a seat, do not adjust the seat to retrieve it.

Seats may crush batteries and cause overheating or fire, IATA warns. Alert cabin crew instead, as they know safe retrieval methods.

The FAA advises checking with your airline, since individual carriers and international standards may exceed U.S. limits. Southwest Airlines, for instance, now restricts passengers to one charger each.

Many airlines publish detailed policies covering various battery types, including those in laptops, tablets, and e-cigarettes.

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