Yes, lithium‑ion batteries are allowed in the cabin when each cell stays under 100 Wh and spares ride only in carry‑on, never in checked bags.
Flying with phones, laptops, drones and power banks is routine, but the cells that power them can ignite if mishandled. Airlines and regulators set watt‑hour limits and packing rules so travelers can bring gadgets without filling the cabin with smoke. This guide lists the allowed sizes, spare‑cell caps and packing steps you must follow to keep the trip smooth. You will also find links to official sources so you can double‑check before leaving for the airport.
Battery Size Rules At A Glance
Regulators use watt‑hours (Wh) to rate lithium‑ion capacity. The figure is printed on every modern cell. The next table shows the limits that apply on most commercial flights.
| Capacity Rating | Typical Devices | Spare‑Cell Limit (Carry‑On) |
|---|---|---|
| ≤ 100 Wh | Phones, cameras, laptops | Unlimited in cabin |
| 101 – 160 Wh | Video lights, medical gear | Two per person with airline OK |
| > 160 Wh | e‑bikes, power stations | Not allowed on passenger flights |
The watt‑hour number decides which rule you follow. If the rating is missing, multiply voltage by amp‑hours to find Wh.
Why Carry‑On Is Mandatory For Spares
Cabin stowage lets crew act fast if smoke appears. In the hold, hidden flames can spread before sensors react. The Federal Aviation Administration states that spare lithium‑ion batteries and power banks must stay in carry‑on, and each terminal needs insulation using tape or sleeves.
Major airlines such as Delta, United and American cap spare cells between 101 Wh and 160 Wh at two per traveler and ask that you tell staff at the gate.
Checked Bags: Installed Batteries Only
Devices with embedded packs—laptops, cameras, toothbrushes—may ride in checked luggage if they are totally switched off. Sleep or hibernation does not count. Close every folding screen, disable wake‑on‑lid and wrap the gadget with clothing to stop switch movement. If the device is recalled or shows damage, leave it off the aircraft entirely.
Packing Checklist
Shield Terminals
Slide every loose cell into a plastic bag or original sleeve. If nothing is available, wrap electrical tape around exposed metal. Never carry a coin cell loose in a pocket with keys.
Use Solid Cases
Hard‑shell cases for camera batteries or power banks stop crushing during turbulence. Pick fire‑retardant fabric when possible and label the outside with the watt‑hour rating.
Know Your Wh
Multiply volts by amp‑hours: an 11.1 V 4400 mAh pack equals 48.8 Wh, safely below the main limit. If the sum exceeds 100 Wh, keep a screenshot of the math for inspectors.
Airline Comparison Table
Carrier rules vary. The next chart compares spare‑cell limits at four large operators.
| Carrier | 101‑160 Wh Spares | Advance Notice? |
|---|---|---|
| Delta | 2 | Yes |
| United | 2 | Yes |
| American | 2 | Yes |
| UK CAA Guidance | 2 | N/A |
If you change planes, follow the strictest rule across the trip. A battery accepted on one leg may be refused on the next if you transit through a region using tighter limits.
International Differences
The International Air Transport Association publishes yearly guidance that most civil authorities adopt, yet local bodies can add clauses. The UK Civil Aviation Authority limits passengers to two large spares, while some Asian carriers ban power banks over 20 000 mAh.
Smart Luggage And Built‑In Cells
Smart suitcases ship with GPS modules, USB ports and a lithium battery hidden in a side wall. Most units use packs of 20‑25 Wh, so they are clear for flight, yet the cabin rule for spares still applies: the cell must be removable. If the frame covers the screws or the pack is soldered, staff may refuse the bag. Before purchase, choose a design that lets you remove the pack in under one minute with a small tool. During check‑in the agent can then confirm removal, tag the shell and place the pack in your hand luggage, meeting airline and TSA rules.
Damaged Or Recalled Packs
Bloated casings, crushed corners or scorch marks are warning signs. Airlines may bar any cell that shows defects because a short can start at low cabin pressure. If your phone or laptop battery swells, replace it before travel. For recalled units, carry proof of the manufacturer repair or the replacement order. Many gate agents keep a list of serial numbers banned from flight, including older MacBook Pro packs. If the item cannot be repaired in time, ship it by ground courier or gift it to a recycling center.
Quick Math: Convert mAh To Wh
Multiply milliamp‑hours by voltage then divide by 1000. A 5000 mAh power bank at 3.7 V works out to 18.5 Wh, under the limit. Most labels list both values, yet older camcorder packs often show only capacity. Keep a note with the calculation to save time at screening. The same formula works for lithium polymer and nickel manganese cobalt variants. It also satisfies curious gate staff.
Screening Tips At Security
Place all spares in a clear zip pouch and drop it in a tray beside your liquids bag. Tell the officer that the pouch contains lithium batteries so they do not run the x‑ray twice. Keep data sheets for exotic cells such as 21700 packs used by photographers. If you travel with a battery‑powered wheelchair, bring the manufacturer spec sheet and mark the disconnect switch with bright tape. Clear labeling and quick answers earn a polite nod and a shorter queue.
Fast Reminders
Scan labels for Wh rating. Remove loose cells from checked luggage. Tape terminals or use sleeves. Carry at most two 101‑160 Wh spares. Declare cells at the gate. Recharge only after the seat belt sign is off. Discard damaged batteries.
Frequently Asked Questions
Can I bring a vape? Yes. Keep it in the cabin and remove spare pods from checked bags. Disable the heating switch and use a protective cap.
Are 26800 mAh power banks allowed? Most are about 100 Wh, so they pass. Models above that mark need carrier approval or must stay home. Check the label before packing.
What about drone batteries? Drone flight packs often sit near 150 Wh. You may carry two spares in the cabin, each in a fireproof bag, and you must discharge them to 30 % state‑of‑charge.
Lithium‑ion cells power nearly all modern gadgets, yet they demand respect. Check the watt‑hour rating, pack spares in the cabin with insulated terminals and keep devices switched off if they travel in checked luggage. Follow these steps and you can fly with your tech and a calm mind.