Michael Turner
International regulations (IATA Dangerous Goods Regulations) and major aviation authorities require that spare lithium metal and lithium‑ion power cells travel in cabin baggage only, with terminals isolated to prevent short circuits. Installed cells inside a device may be transported in the hold, but detachable spares must remain in the passenger cabin for safety and screening.
Most disposable button cells used for assistive ear devices–common sizes 10, 13, 312, 675–use zinc‑air chemistry and are not classified the same as lithium cells; nevertheless, screening and risk‑management practices favor carrying all spare cells in carry‑on. Rechargeable packs that use lithium‑ion chemistry are explicitly subject to cabin‑only rules and per‑cell capacity or quantity limits imposed by airlines and state regulators.
Follow this practical checklist before travel: keep spares in original packaging or dedicated battery cases; insulate exposed terminals with tape or individual sleeves; leave cells installed if possible and switch devices fully off; segregate all spare power cells from other metallic items; place spares where they can be shown quickly during security screening. Present medical devices separately during inspection if requested by security staff.
Airline and national rules vary–verify the specific carrier policy and destination country limits prior to departure. Flight crews and ground agents retain final authority at the airport; failure to follow carrier directives may result in removal of the spares or denial of carriage. When in doubt, contact the airline’s dangerous‑goods or accessibility desk for written guidance before travelling.
TSA and IATA rules: are lithium and button cells allowed in aircraft hold?
Recommendation: carry spare lithium-metal and lithium-ion cells in the cabin only; leave installed cells inside assistive auditory devices where possible and protect terminals with tape or original packaging before placing devices in the aircraft hold.
- TSA summary: spare lithium cells are forbidden in the aircraft hold and must travel in carry-on. Cells installed in equipment are generally permitted both in the cabin and in the aircraft hold, but TSA advises keeping devices with lithium cells in the cabin when feasible.
- IATA standards (applies to most airlines): spare lithium-ion cells under 100 Wh and lithium-metal cells with ≤2 g lithium content per cell may be carried in the cabin; lithium-ion cells between 100–160 Wh require airline approval and are limited to two per passenger; cells above 160 Wh are prohibited for passenger carriage.
- Button-type zinc‑air cells (common for assistive auditory devices – sizes 10/312/13/675) are non‑lithium and normally allowed both in cabin and aircraft hold; nevertheless, keeping spares in the cabin avoids loss and simplifies screening.
- Terminal protection: insulate exposed terminals (tape or individual plastic covers) and place spares in a dedicated pouch or original retail packaging to prevent short circuits; IATA and TSA require effective short‑circuit protection for all spare cells carried in the cabin.
- Airline variances: carriers may impose stricter limits (quantity, packaging, or total Wh); confirm with the airline before departure and declare cells that exceed 100 Wh or any unusual power cell type.
Practical checklist
- Keep spares in the cabin in a zipped pouch; label if necessary.
- Leave primary cell inside the device when possible; power device off and protect controls.
- Tape terminals or use original blister packs for spares; place each cell separated to avoid contact.
- If a cell is >100 Wh or >2 g lithium, obtain written airline approval before travel.
- Carry a small GPS tag in checked items for tracking (example resource: best luggage gps tags), and for maintenance/cleaning options consult guides like best freshner for washing machines when preparing cases or travel pouches.
How to store zinc‑air button cells: protecting terminals, using original blisters, and preventing activation
Keep zinc‑air button cells inside the manufacturer’s sealed blister until immediate insertion; do not remove the vent tab or expose to air prior to use.
Terminal protection
Prevent terminal-to-terminal contact by leaving cells in individual blister cavities or placing each cell in a small rigid plastic carrier. If loose transport is unavoidable, cover both terminals with a single layer of PVC electrical tape (no metal clips), or use purpose-made clear silicone caps that fully insulate the flat faces. Avoid paper or thin cloth alone; these can shift and allow shorting.
Using original blisters and preventing activation
Retain original blister cards or trays and reseal opened boxes with low‑tack adhesive labels showing manufacture date. Do not remove the adhesive/activation tab until immediately before insertion into a device; once the tab is removed, life expectancy is typically measured in days rather than years. Store sealed blisters at 10–25°C and relative humidity under 60% to preserve shelf life (sealed shelf life commonly 3–5 years depending on manufacturer). For transit, use a rigid outer container sized to prevent movement (examples of compact rigid cases are available – see best inverted umbrella jumbo) and place foam or cardboard dividers to stop blister flexing.
Label containers clearly with cell chemistry (“zinc‑air”), size (e.g., 312, 10, 13, 675), and quantity. Avoid mixing different sizes or chemistries in one compartment. Do not puncture vent holes, coat terminals with conductive grease, or store near metal objects that could bridge terminals. For single spare cells, a heat‑shrink insulated sleeve or commercial multi‑cell plastic case is the safest option.
Rechargeable lithium cells for in-ear devices: watt‑hour limits, terminal protection, and airline notification
Recommendation: Keep rechargeable lithium‑ion cells installed in the device when possible and transported in the aircraft cabin; spare cells must have terminals insulated and be carried in protective packaging; any cell with a rating above 100 Wh but not exceeding 160 Wh requires written airline approval; cells over 160 Wh are not permitted on passenger flights.
Watt‑hour measurement and thresholds
Calculate capacity with: Wh = V × Ah (convert mAh to Ah by dividing by 1,000). Example: 3.7 V × 30 mAh (0.030 Ah) = 0.111 Wh. Regulatory breakpoints: below 100 Wh – generally allowed in cabin without prior approval; 100 Wh to 160 Wh – airline approval required (typically limited to two spare cells per passenger); above 160 Wh – forbidden for carriage on passenger aircraft. Keep manufacturer data sheets or label showing voltage and capacity available for inspection.
Terminal protection and airline notification
Terminal protection: Apply non-conductive tape over exposed terminals or use manufacturer terminal caps. Place each spare cell in an individual plastic bag or rigid case to prevent contact with metal objects and movement. Use original retail packaging if available. Ensure the device is powered off and any removable cells installed in the device are secure to prevent shorting or activation.
Notification procedure: For cells rated >100 Wh and ≤160 Wh, contact the carrier well before travel (allow at least 48 hours) and provide manufacturer, model, Wh rating and quantity. Request written approval and retain a copy for check-in and security checks. At airport processing present the approval and the cells in their protective packaging; expect security personnel to ask for removal of installed cells for inspection. If documentation cannot be produced, the carrier may refuse carriage.
Practical airport steps: declaring spares, carry‑on best practices, handling confiscation or damage
Declare spare power cells immediately at airline check-in or security screening and keep all spares inside carry‑on baggage; present them separately, in original blister packs when possible, or with terminals insulated (tape or terminal caps) and placed in a clear resealable bag for X‑ray.
At check‑in and security – exact steps
Tell the counter or security officer: “I have spare button and rechargeable power cells for personal use, in original packaging/with taped terminals.” Hand over only what is requested for screening and avoid mixing with electronics. If any cells exceed manufacturer-specified size or show visible damage, disclose that fact and hand them to staff rather than attempting to conceal them.
Carry documentation: a brief printed note listing cell types (zinc‑air button, Li‑ion removable), quantities, and Wh rating for rechargeable units; keep product packaging or a copy of manufacturer specs handy. If an airline requires pre‑approval for higher‑capacity rechargeable units, secure that approval during booking or at check‑in and show the confirmation to staff.
Best practice inside carry‑on
Store spares in a small hard or crush‑resistant case inside the main carry‑on compartment to prevent crushing and short circuits. For button cells, leave in original blisters; if removed, tape both terminals and separate cells with foam or individual compartments. For removable Li‑ion cells, use insulated sleeves or dedicated battery cases and label each with its Wh rating if known.
Limit quantities to a personal‑use amount; avoid loose contact with metal objects (coins, keys, jewelry). Keep spares accessible for screening staff without digging through packed items. If traveling internationally, carry a single list of the spares and any airline approvals to avoid repeated questions during transfers.
If confiscated or damaged – immediate actions
If an item is seized, request a written confiscation receipt or property form, take a photo of the item and the receipt, and obtain contact details for the security or airline office handling the seizure. Ask whether retrieval or courier return is permitted; many airports will not allow hazardous items to be mailed, so plan for replacements at destination if needed.
For visibly damaged or leaking power cells: move the item into a non‑conductive container (plastic jar or bucket), wear gloves, avoid direct skin contact with any leakage, and inform staff immediately so trained personnel can handle disposal. Do not attempt to reassemble, charge, or use a damaged cell.
After the flight, file a written complaint with the airline or airport authority if documentation was not provided or if compensation is sought; include photos, receipts, boarding pass, and the confiscation form. Contact the manufacturer for warranty or replacement guidance for any damaged units; retain all evidence until the claim is resolved.
