Can I Bring Batteries on a Plane?

Key restrictions

Spare lithium batteries (loose, not in a device) are carry-on only — banned from checked luggage.

Lithium-ion spares up to 100Wh fly without approval; 100–160Wh need airline approval, usually two maximum.

Lithium batteries over 160Wh are prohibited on passenger flights.

Lithium metal spares are limited to 2 grams of lithium content (covers standard camera and coin cells).

Alkaline and standard NiMH rechargeables (AA, AAA, C, D, 9V) are allowed in both carry-on and checked bags.

Protect spare battery terminals — original packaging, tape over contacts, or separate pouches.

Why this matters

Batteries are the most fire-prone thing in an ordinary suitcase. Lithium cells that are crushed, punctured, or short-circuited can enter thermal runaway — a self-sustaining fire that aircraft cargo-hold suppression systems are not designed to stop. That is why the rules sort batteries by chemistry and by whether they are loose or installed, and why the carry-on-only rule for spares is enforced on every airline in the world.

Restrictions

The key question is what kind of battery, and where it is:

Spare lithium-ion (loose power banks, camera batteries, laptop spares): carry-on only. Up to 100Wh needs no approval; 100–160Wh needs airline approval and is normally capped at two; over 160Wh cannot fly on passenger aircraft.
Spare lithium metal (non-rechargeable, like CR123 or coin cells): carry-on only, up to 2g of lithium content per battery.
Installed batteries: devices with batteries inside may go in carry-on or checked bags, though checked devices must be fully powered off and the FAA recommends keeping them in the cabin.
Alkaline, NiMH, NiCad (AA, AAA, C, D, 9V): allowed in both carry-on and checked baggage without special limits.

All spares should have terminals protected — taped, bagged individually, or kept in retail packaging. Quantity should be reasonable for personal use; bulk quantities look commercial and can be refused.

What the official guidance says

The FAA's PackSafe guidance requires spare lithium batteries in carry-on baggage with terminals protected from short circuit, sets the 100Wh and 160Wh thresholds for lithium-ion and the 2g limit for lithium metal, and permits dry-cell alkaline batteries in either bag. TSA applies the same framework at screening, and individual airlines may impose stricter counts, so check your carrier for anything beyond a handful of spares.

Frequently asked questions

Can AA or AAA batteries go in checked luggage?

Yes. Ordinary alkaline and standard consumer rechargeable batteries (NiMH, NiCad) are allowed in both carry-on and checked bags with no quantity limit for personal use. The carry-on-only rule targets lithium batteries specifically.

Why are spare lithium batteries banned from checked bags?

Damaged or short-circuited lithium batteries can ignite, and a fire in the cargo hold cannot be reached by the crew. In the cabin, a battery fire can be spotted and extinguished quickly, which is why regulators worldwide require spares to fly with you.

How should I pack spare batteries?

Keep them in original retail packaging, tape over the terminals, or place each battery in its own plastic bag or protective case. The goal is preventing terminals from touching metal objects like keys or coins, which can cause a short circuit.