TIANQIUShort answer: yes for alkaline, yes with conditions for lithium. The rules that catch travellers out are not about whether batteries are allowed, but about where they are packed and how their terminals are protected.
Which batteries can go in which bag?
Two questions settle the table below: which chemistry is in the cell, and whether it is installed in a device or carried loose as a spare. Alkaline and zinc-carbon cells are ordinary consumer goods in either bag; lithium cells are regulated goods, and their spare units are the case airlines treat most strictly.
| Battery type | Carry-on | Checked baggage | Condition that applies |
|---|---|---|---|
| AA / AAA / C / D / 9 V alkaline and zinc-carbon | Yes | Yes | No watt-hour limit; keep in original packaging or tape the terminals |
| Coin cell fitted in a device (CR2032, CR2025, CR2016) | Yes | Usually yes | The device holds the cell and covers its terminals |
| Spare coin cells — lithium metal (CR2032 and other CR cells) | Yes, terminals protected | Often restricted — airline-dependent | Carry-on is the route accepted without exception; keep the cell on its retail card or tape it |
| Spare lithium-ion batteries and power banks | Yes — carry-on only | Not allowed | Never in the hold, at any capacity |
| Lithium-ion installed in a device (laptop, camera, toy) | Yes | Usually yes | Only a contained, protected unit counts as “installed” |
| Above the common 100 Wh threshold | Airline approval required | Airline approval required | Ask the carrier before travel |
Read the table this way: alkaline and zinc-carbon cells are treated as ordinary consumer goods, so nothing changes for them. Lithium is where the rules tighten — and a spare lithium cell is treated more strictly than one fitted inside a device, because the device protects its own terminals. Watt-hours only enter the picture for lithium-ion.
Are CR2032 batteries allowed in checked baggage?
A CR2032 is a lithium metal cell, so it is not treated like an ordinary alkaline cell. Spare CR2032s belong in carry-on with the terminals protected — many airlines restrict loose lithium cells in checked baggage. A CR2032 fitted in a device travels fine in a checked bag, because the device holds the cell and covers its terminals.
Our CR2032 model page lists the specifications if you need to confirm what type of cell you are carrying.
Can you fly with alkaline and carbon-zinc cells?
Yes — standard alkaline and zinc-carbon cells count as ordinary consumer goods, so no watt-hour ceiling applies and neither bag is off limits. What does vary is how a carrier wants them packed, which is why the three points below are the ones security actually checks for:
- allowed in both carry-on and checked baggage,
- no watt-hour limit for the cells themselves,
- best transported in their original packaging or with the terminals taped, so they cannot short against keys or coins.
What are the rules for lithium cells and batteries?
Lithium is where the rules tighten, because a shorted lithium cell can heat, vent and ignite, and a spare cell has no device around it to stop that. The table below separates the four cases that matter — installed versus spare, lithium-ion versus lithium metal — because each one lands in a different bag:
| Item | Carry-on | Checked |
|---|---|---|
| Installed in a device (laptop, camera, toy) | Yes | Usually yes |
| Spare lithium-ion batteries / power banks | Yes — carry-on only | Not allowed |
| Spare lithium metal cells (CR2032 and other coin cells) | Yes, terminals protected | Airline-dependent, often restricted |
| Above the common 100 Wh threshold | Airline approval required | Airline approval required |
Pack spare lithium cells in carry-on. That is the rule most airlines apply without exception, and it is also what security expects to see when a bag is opened. It applies to every CR coin cell, not only the CR2032 — the CR2025 and CR2016 travel under exactly the same rule.
What are the 2 g and 100 Wh limits?
Two ceilings decide whether a cell travels without paperwork: non-rechargeable lithium cells are capped at 2 g of lithium content, and rechargeable lithium-ion batteries at 100 Wh per battery. Both come from the dangerous-goods rules that airlines work to, and both are read off the cell’s marking or data sheet — not estimated from its size.
| Limit | What it measures | Which cells it covers | Above the limit |
|---|---|---|---|
| 2 g lithium content | grams of lithium metal sealed inside the cell | Non-rechargeable lithium: CR2032, CR2025, CR123A | Up to 8 g with airline approval, maximum two spares per passenger |
| 100 Wh per battery | Energy rating, volts × amp-hours | Lithium-ion: power banks, laptop and camera packs | 101–160 Wh with airline approval, maximum two spares per passenger |
| No watt-hour limit | — | AA, AAA, C, D and 9 V alkaline and zinc-carbon | Nothing to declare; ordinary consumer goods |
Two details catch travellers who have read only the headline. The first is that the ceiling applies to each battery, not to the bag — five 20,000 mAh power banks are each legal on their own, though many airlines impose their own count limit on power banks regardless of Wh, so the carrier’s page is the last word. The second is the ceiling on purpose: cells carried for sale or distribution, including vendor samples, are not personal-use batteries and are prohibited in passenger baggage altogether — which is why a sample request travels as freight with its documents, under the lithium battery shipping requirements, not in a suitcase.
The figures above are the ones the FAA publishes for flights to and from the United States; the ICAO and IATA rules that most other countries apply use the same 2 g and 100 Wh ceilings, and an individual airline can always be stricter than both.
For the cells we make, neither limit is close. Our CR2032 line is rated 190–255 mAh at 3 V, which works out to 0.57–0.765 Wh, and the lithium content of a coin cell is a fraction of the 2 g allowance — the exact figure sits in section 9 of the safety data sheet, which is why the MSDS is worth keeping with the cell.
How do you work out the watt-hours of a power bank?
Watt-hours are volts multiplied by amp-hours, so a pack marked 20,000 mAh at 3.7 V is 20 Ah × 3.7 V ≈ 74 Wh — comfortably inside the 100 Wh ceiling. The number that governs is the one printed on the pack itself, not the capacity of the phone it charges, and each chemistry multiplies out differently.
| Pack or cell | Volts | Amp-hours | Watt-hours | Under the 100 Wh ceiling? |
|---|---|---|---|---|
| CR2032 coin cell, our line | 3 V | 0.19–0.255 Ah | 0.57–0.765 Wh | Yes, by a wide margin |
| AA alkaline, our line | 1.5 V | 2.15–2.6 Ah | 3.2–3.9 Wh | Not subject to the limit |
| Power bank, 10,000 mAh | 3.7 V | 10 Ah | 37 Wh | Yes |
| Power bank, 20,000 mAh | 3.7 V | 20 Ah | 74 Wh | Yes |
| Power bank, 27,000 mAh | 3.7 V | 27 Ah | ~100 Wh | At the ceiling — read the label |
The arithmetic is only a cross-check: a pack sold legally carries its own Wh rating on the case, and that printed figure is what a security officer reads. Where a pack states only mAh, multiply by its nominal voltage before deciding whether it needs airline approval. Cells that travel as cargo rather than as luggage are tested to the transport standards instead, which is what the UN38.3 test summary covers for the lithium cells we ship.
How should you pack cells so they pass inspection?
- Keep cells in their retail packaging if you have it — it is designed to prevent contact.
- Tape the terminals of loose cells with insulating tape, or put each one in a small plastic bag.
- Do not leave loose cells in a pocket of a bag with metal objects.
- Check the Wh rating printed on lithium-ion batteries and power banks; the 100 Wh figure is the threshold most carriers use before requiring approval.
- Declare what you must — if a carrier asks for the battery type, say lithium-ion or lithium metal rather than “batteries”.
How are batteries shipped commercially?
For cargo, the paperwork matters more than the packing: lithium cells travel under UN38.3 test reports with an MSDS and transport documentation, and air or sea freight has different declarations. That documentation is prepared per shipment, and it is one of the things we supply with every battery order.
What is declared on the commercial invoice, and how freight and duties are allocated, is set out in our shipping policy; cells and packs that travel as cargo are built in the lithium battery programme, and the document set per destination is covered in the battery FAQ.