Michael Turner
Do not place loose coin or button cells inside a stowed suitcase; keep spares with you in the passenger cabin and leave cells installed in devices when possible.
Many common coin cells (for example CR2032) contain roughly 0.13 g of metallic lithium per cell. International air transport rules set a limit of 2 g lithium metal per cell for passenger carriage. Rechargeable lithium-ion packs rated above 100 Wh need airline approval when carried, and packs over 160 Wh are forbidden on passenger aircraft.
Prevent short circuits by keeping spares in original retail packaging, covering terminals with non-conductive tape, or using insulated pouches; store each cell separately and avoid contact with keys, coins or chargers. Devices with installed cells should be powered off and protected against accidental activation before being stowed.
Check the carrier’s policy and the applicable civil aviation rules before travel; declare large-capacity power sources to the airline during booking or check-in if required. If unsure, transport spare cells in the cabin and carry devices with irreplaceable cells onboard.
Permitted cell chemistries for hold baggage
Recommendation: avoid placing lithium cells in the aircraft hold whenever possible; silver‑oxide and alkaline coin cells installed in devices are generally acceptable in the hold, but loose lithium cells (spares) should be carried in the cabin.
Lithium (metal and lithium‑ion): rechargeable lithium‑ion units are regulated by watt‑hour (Wh) rating – cells up to 100 Wh are normally allowed when installed in equipment; cells between 100 Wh and 160 Wh require airline approval; >160 Wh are prohibited on passenger flights. Non‑rechargeable lithium metal coin cells (e.g., CR series) are heavily restricted as spares: most carriers insist spares remain in the cabin. If a lithium cell is installed in a device that will be placed in the hold, power the device off and protect against accidental activation; still check the carrier’s policy before packing.
Silver‑oxide (button/coin) cells: common timepiece silver‑oxide cells are typically permitted both installed in devices and as loose spares in hold baggage, but terminals must be insulated. Keep cells in original packaging or place each cell in a separate plastic case or wrap terminals with nonconductive tape to prevent short circuits.
Alkaline coin and cylindrical cells: standard alkaline cells present low thermal/runaway risk and are usually allowed in the hold whether installed or loose. Apply the same terminal protection rules as for silver‑oxide cells and avoid bulk loose storage where contacts can bridge.
Packing recommendations applicable to all chemistries: protect terminals (original packaging, individual pouches, or tape), place spares in carry‑on if lithium, power devices off, and separate cells from metal objects. Verify both the airline’s policy and applicable national aviation authority rules before departure; airline staff have final authority at check‑in.
Are spare lithium coin/button cells permitted in the cabin or must they go in the aircraft hold?
Keep all spare lithium coin/button cells in carry-on (cabin) baggage; do not pack loose spares in the aircraft hold.
- Regulatory baseline: FAA, IATA and EASA require spare lithium metal and lithium‑ion cells to be carried in the cabin; spares are not permitted in the aircraft hold.
- Lithium metal (non‑rechargeable) coin/button cells: maximum lithium content allowed is 2.0 g of lithium per cell. Any cell exceeding 2.0 g is prohibited on passenger aircraft.
- Lithium‑ion (rechargeable) cells: capacity is measured in watt‑hours (Wh). Spares ≤100 Wh are permitted in the cabin without airline approval. Cells >100 Wh and ≤160 Wh require airline approval and are usually limited to two spares per passenger. Cells >160 Wh are not allowed on passenger aircraft.
- Quantity guidance: there is no universal numeric limit for small coin cells under regulatory thresholds, but many carriers apply operational limits – check carrier policy ahead of travel.
Packing and handling checklist:
- Insulate terminals: cover exposed terminals with non‑conductive tape or keep cells in original retail packaging or individual plastic cases to prevent short circuits.
- Separate storage: store each spare cell separately or in compartments; avoid loose storage with metal objects (coins, keys).
- Accessibility: keep spares in hand luggage so they remain available for security inspection and crew queries.
- Large quantities or commercial shipments: move via approved cargo channels or a specialist courier under dangerous goods procedures rather than as passenger carriage.
Verify carrier and destination rules before departure; national or airline policies may add restrictions–see an example of destination-specific guidance here: are drones allowed in switzerland.
How to pack a timepiece with an installed coin cell in the aircraft hold to prevent short circuits and damage
Place the timepiece in a rigid, padded case and position that case in the aircraft hold surrounded by soft clothing; keep it away from heavy or sharp items.
Push the crown fully in or screw it down; fasten the clasp so the bracelet cannot flap and create impact points. Do not open the case back or attempt to remove the installed cell before travel.
Use a purpose-made travel case with foam cutouts sized to the case diameter (2–5 mm clearance around the case). If no travel case is available, wrap the timepiece twice in bubble wrap (minimum 2× 3/16″ bubbles) and put it into a small rigid box or hard-shell container.
Place the wrapped item inside a sealable plastic bag with a silica gel packet to reduce condensation. Lay the timepiece face-up to reduce pressure on the crystal; secure any loose links with a soft cloth or foam wedge so lateral movement is under 5 mm.
Avoid contact with metal tools, keys, coins or toiletries. If any metal surfaces are exposed (for example, removable straps or quick-release pins), isolate them in individual pouches or apply a single layer of non-conductive tape to cover sharp edges–do not tape directly over crowns or pushers.
For extra protection choose a hard-sided suitcase or add a padded insert; compare protective options like best luggage guardian. High-value or vintage pieces are safer in carry-on; for stowed transport, place the padded case in the center of the bag, surrounded by soft garments and away from the bag shell to minimize shock transmission.
How to verify airline and international rules before packing coin/button cells for a trip
Immediately consult the carrier’s dangerous-goods page and the latest IATA Dangerous Goods Regulations and ICAO Technical Instructions; have cell chemistry, model numbers, capacity (Wh or mAh) and quantity documented before departure.
Authoritative sources to check: the airline’s DG policy, the origin and destination civil aviation authority websites (FAA, EASA, CAA, etc.), and customs/import regulations for transit countries. Search site terms: “dangerous goods”, “lithium cell”, “portable electronic device”, “spare lithium”, and the specific cell model number.
Prepare a one-page factsheet for each cell type: chemistry (lithium metal, lithium-ion, silver-oxide, alkaline), cell designation (CR2032, LR44, etc.), capacity in mAh or Wh, lithium content in grams (if applicable), manufacturer safety data sheet (SDS/MSDS) and original packaging photos. Keep digital and printed copies accessible during check-in and security screening.
Contact the airline’s reservations or hazardous-goods desk at least 48–72 hours before travel and request written confirmation when restrictions or approvals are unclear. Provide this script: “Traveling on flight [number] from [origin] to [destination] with [quantity] [cell type/model]. Please confirm required approvals, packaging, and whether connecting carriers have additional rules.” Ask for any required entry in the booking record or special handling code.
Verify whether the route involves multiple carriers or transit through countries with separate rules; require confirmations from each carrier if connections are managed by different airlines. Save screenshots or PDFs of policies and any email approval; present them at check-in if asked.
If planning to ship cells instead of carrying them in personal baggage, consult postal and courier dangerous-goods guides and complete required declarations and labeling. For commercial shipments, obtain a Dangerous Goods Note and confirm acceptance with the carrier’s DG office before tendering the parcel.
Travel steps for carrying multiple spare coin or button cells and transporting replacements bought abroad
Recommendation: Pack spare coin/button cells in their original sealed retail blister or in individual plastic holders with each terminal insulated, carry clear purchase receipts and product datasheets on your phone, and limit quantities to what you need for the trip (a practical guideline: up to a dozen per model for extended stays).
Packing checklist
1. Keep cells in original retail packaging whenever possible; that packaging is designed to prevent terminal contact. If original packs are unavailable, use rigid plastic coin cases or wrap each cell terminal with Kapton or electrical tape so no metal-to-metal contact can occur.
2. Group cells by model and voltage (e.g., CR2032 – 3.0V). Put each group into a small hard-sided container inside your hand bag to minimise crushing and movement. Place a paper label inside the container with model, chemistry, voltage and quantity.
3. Do not mix loose cells with coins, keys, cables or metal objects. Add a thin foam divider or plastic tray between layers if carrying multiple stacks.
4. For cells that will power a timepiece already packed, leave installed cells inside the device when feasible; protect the device from pressure and impact with padded wrap.
5. Remove and isolate any damaged, swollen or leaking cells. Place them in a sealed plastic bag and present them to airline or security staff for guidance rather than attempting to transport them yourself.
Steps when purchasing replacements abroad
1. Request sealed retail packaging and an itemised receipt that shows model numbers, quantity and seller contact details. Ask the vendor for a product datasheet or SDS; if unavailable, photograph labels and packaging before leaving the store.
2. Verify voltage and chemistry on the package; write this information into a notes app or save photographed labels as PDFs to show security or customs if questioned.
3. If your purchase exceeds a personal-use amount or you plan to send cells home, use a specialist courier that accepts battery shipments and offers dangerous-goods packaging and declarations. Do not place large quantities in postal envelopes without carrier approval.
4. Keep purchases accessible in your carry items until you have cleared departure security; unexpected queries are often resolved faster when documentation and packaging are immediately available.
Quick tools to carry: small hard coin case, roll of Kapton/electrical tape, zip-seal bags, phone folder with PDFs of receipts and datasheets.
FAQ:
Can I pack spare watch batteries in checked luggage?
Most airlines and aviation rules require spare lithium watch cells to be carried in the cabin, not in checked bags, because loose batteries can short and start a fire. If you only have non-lithium types (for example standard silver-oxide cells), rules are less strict but airport security or an airline may still prefer them in carry-on. Best course: keep spare batteries with you in carry-on, keep terminals covered or in original packaging, and confirm any carrier-specific limits before travel.
Are watch batteries that are already installed in a watch allowed in checked baggage?
Watches with their batteries installed are generally allowed in checked baggage. Carriers normally treat installed cells as lower risk than loose spares. Still, secure the watch so it cannot turn on accidentally and, if the item is valuable, consider carrying it in the cabin to reduce risk of loss or damage. If you have any doubts, check the airline’s guidance or ask airport security staff.
Which types of watch batteries are most likely to be restricted for air travel?
Lithium button cells (examples include CR-series lithium coin cells) are the ones most often subject to limits because of their chemical energy and potential for thermal events if shorted. Rechargeable lithium-ion packs are also tightly regulated. Silver-oxide and alkaline button cells pose lower hazard and are usually allowed with fewer conditions, but screening policies vary. Because rules differ by regulator and airline, check the carrier’s battery policy and the relevant aviation authority before flying.
How should I pack extra watch batteries to reduce risk and avoid problems at security checkpoints?
Pack spares in your carry-on rather than checked baggage whenever possible. Keep them in their original retail packaging or place each cell in a small plastic case or separate compartment so the terminals cannot contact metal objects. Alternatively, cover terminals with tape. Limit the number of spare batteries to what seems reasonable for personal use; if you need a large quantity, contact the airline ahead of time and be prepared to declare them. At the checkpoint remove batteries if asked and present them separately. Confirm specific quantity limits and packing rules on the airline website or the site of the aviation regulator for your departure country before you travel.
