Battery packs are allowed on planes, but only in your carry-on bag, and only if they meet specific size limits

The TSA (Transportation Security Administration) and most airlines permit lithium battery packs in carry-on luggage, but they must be under 100 watt-hours (Wh). This covers most phone chargers, small power banks, and portable device batteries. Batteries larger than 100 Wh are prohibited entirely on passenger aircraft. You cannot pack any battery packs in checked baggage — they must travel with you in the cabin.

The reason for this rule is fire risk. Lithium batteries can overheat and ignite if damaged or short-circuited, and a fire in the cargo hold is harder to detect and fight than one in the passenger cabin. The TSA and Federal Aviation Administration (FAA) treat battery packs as dangerous goods, which is why the rules are strict and consistent across nearly all U.S. carriers.

Different airlines sometimes add their own limits on top of the federal rules, so checking your specific airline's website before you pack is the safest step. Some carriers allow only one or two battery packs per passenger, while others are more lenient. A quick call to the airline or a look at their baggage policy page takes five minutes and prevents problems at the gate.

Key Takeaways

  • Battery packs under 100 watt-hours are permitted in carry-on bags only; anything larger is banned from passenger aircraft.
  • Battery packs must never go in checked baggage, even if they are small — they belong in your carry-on or personal item.
  • Most phone chargers and portable power banks fall well under the 100 Wh limit, but larger camping or vehicle batteries do not.
  • Your airline may have stricter rules than the TSA, so confirm their policy before arriving at the airport.
  • Damaged, recalled, or swollen batteries should not be brought on any flight — contact the manufacturer or dispose of them safely first.

How to check the watt-hour rating on your battery pack

The watt-hour (Wh) rating is usually printed on a label on the back or bottom of the battery pack. Look for a number followed by "Wh" or "Watt-hours." If you see milliamp-hours (mAh) instead, you can convert it roughly: divide the mAh number by 1,000, then divide by the voltage (usually 3.7V for lithium batteries). For example, a 20,000 mAh battery at 3.7V is about 74 Wh, which is under the limit.

If the label is worn or missing, contact the manufacturer with the model number. Do not guess — bringing an oversized battery onto a plane can result in confiscation, fines, or being banned from the airline. Most manufacturers list specifications on their website or in the product manual.

What counts as a battery pack for TSA purposes

A battery pack is any portable device designed to store and release electrical power. This includes phone chargers with built-in batteries, portable power banks, laptop batteries (if removed from the device), and external batteries for cameras or drones. A battery installed inside a working device — like a smartphone, laptop, or camera — is treated differently and is generally permitted without the same size restrictions.

Spare batteries and battery packs that are not installed in a device must follow the 100 Wh rule. If you are bringing a laptop, the battery can stay inside it. If you are bringing a spare laptop battery, it must be under 100 Wh and must go in carry-on baggage.

Damaged or recalled batteries and what to do with them

Do not bring any battery that is swollen, cracked, leaking, or recalled on a flight. Check the manufacturer's website or the Consumer Product Safety Commission (CPSC) website to see if your battery has been recalled. If it has, the manufacturer usually offers a replacement or refund — use that instead of flying with the faulty unit.

If your battery is damaged, take it to a battery recycling center or an electronics retailer that accepts batteries (many Best Buy and Best Buy Mobile locations do). Never throw a lithium battery in the trash or leave it in a car, as it can catch fire.

International flights and airline-specific rules

The 100 Wh limit applies to flights within the United States and most international flights departing from U.S. airports. However, some countries and airlines have stricter rules. If you are flying internationally, check the rules for both your departure airport and your destination country.

Airlines operating under different regulations — particularly carriers based in Europe or Asia — may allow only one battery pack per passenger or may set a lower watt-hour limit. Budget airlines sometimes have tighter restrictions than full-service carriers. Call your airline or visit their website to confirm before you pack.

What happens if TSA finds a battery pack in checked baggage

If a battery pack is discovered in checked baggage during screening, the TSA will remove it and may confiscate it. You will not be able to retrieve it before your flight. In some cases, the airline may refuse to let you board, or you may face a fine. The TSA does not always catch every battery in checked bags, but the risk of fire and the potential consequences make it not worth the gamble.

If you realize after checking a bag that you packed a battery, tell a TSA agent or airline representative when ready. Some airlines will retrieve the bag and remove the battery before it is loaded onto the aircraft.

Frequently Asked Questions

Can I bring a battery pack on a plane if it is inside my laptop or phone?

Yes. Batteries installed inside working devices are permitted in both carry-on and checked baggage. Only spare or standalone battery packs must go in carry-on and must be under 100 Wh. If you are removing a battery from a device to travel with it separately, it counts as a spare battery and must follow the 100 Wh rule.

What is the difference between watt-hours and milliamp-hours?

Watt-hours (Wh) is the standard the TSA uses. Milliamp-hours (mAh) is a different measurement. To convert mAh to Wh, divide the mAh by 1,000, then multiply by the voltage (usually 3.7V for lithium). A 20,000 mAh battery is roughly 74 Wh. If you cannot find the Wh rating, contact the manufacturer.

Can I bring multiple battery packs as long as they are each under 100 Wh?

Most airlines allow two or three battery packs per passenger, as long as each one is under 100 Wh. However, some carriers limit you to one. Check your airline's policy before packing. Even if you are allowed multiple packs, they must all go in your carry-on bag.

Are rechargeable batteries different from disposable ones?

Lithium rechargeable batteries (the kind in most modern devices) are the ones the TSA restricts. Alkaline batteries like AA or AAA are not restricted and can go in checked or carry-on baggage. If you are unsure what type your battery is, check the label or the product manual.

What should I do if my battery pack is on a recall list?

Do not bring it on a flight. Contact the manufacturer to arrange a replacement or refund. If you need a working battery for your trip, buy a new one that is not recalled. Recalled batteries can overheat or catch fire, and airlines take this very seriously.