Why Lithium Batteries and Power Banks Must Go in Your Carry-On

By Travelog Editorial Team ยท Updated August 9, 2026

A lithium battery installed and turned off inside a device (a laptop, phone, or camera) is allowed in checked baggage. A spare battery not installed in a device -- including every power bank, since a power bank itself counts as a spare battery, not an installed one -- must go in carry-on and is banned from checked luggage entirely. Spare batteries also need their terminals protected from short-circuiting, either in original retail packaging or with tape over the contacts.

"Just keep your electronics in your carry-on" is close to the actual rule but not precise about why, and the actual line between what's allowed checked and what isn't trips up more travelers than the basic 3-1-1 liquids rule does, because the distinction depends on a specific technical detail: whether a battery is installed or spare.

The Specific Distinction: Installed vs. Spare

This is the single detail that governs everything else on this page. A lithium battery that's physically installed inside a device -- a laptop, phone, tablet, or camera -- and remains installed (with the device itself powered off) is allowed in checked baggage. A spare battery, meaning any lithium battery not currently installed in a device, is a genuinely different category and must travel in carry-on only. The detail that catches travelers off guard: a power bank counts as a spare battery under this rule, not as an "installed" one, even though it functions as a self-contained device -- there's no exception carved out for power banks specifically, because their entire purpose is storing charge separately from any other device.

Why Terminal Protection Matters for Spare Batteries

This is a specific requirement beyond simply "keep it in carry-on." Spare batteries need their terminals protected from contact with metal objects or other batteries, since an exposed terminal touching another conductive surface can cause a short circuit -- one of the mechanisms behind battery thermal events. The practical compliance methods: keeping a spare battery in its original retail packaging (which typically already isolates the terminals), placing individual tape over exposed contacts, or using a dedicated battery case designed for this purpose. This isn't a formality airlines rarely enforce -- it's a genuine, checkable safety requirement tied directly to why the carry-on rule exists in the first place.

Specific Watt-Hour Limits

Beyond the installed/spare distinction, a separate numeric limit governs battery size. Lithium-ion (rechargeable) batteries rated 100 watt-hours (Wh) or less require no special airline approval and can be carried on freely, within reason. Batteries rated 101 to 160 Wh require the airline's advance approval and are capped at two spares per passenger. Anything exceeding 160 Wh is prohibited from passenger aircraft entirely, with no approval process available. Most consumer power banks and device batteries fall comfortably under the 100 Wh threshold, but larger camera, drone, and specialized-equipment batteries can exceed it without that being obvious from the device's physical size alone -- worth checking a battery's printed Wh rating directly before a trip involving that kind of equipment.

Airline-Specific Differences Worth Checking

While TSA and the FAA set the baseline federal rules, individual airlines can add their own additional restrictions on top of that baseline, and these genuinely differ carrier to carrier. American Airlines, for instance, permits batteries up to 100 Wh in carry-on without special approval but requires travelers to contact the airline in advance for anything in the 100-160 Wh range -- and while American allows devices with installed batteries in checked baggage, the airline's own guidance recommends keeping electronics in the cabin regardless. Delta's published guidance allows carrying a specific quantity of spare batteries -- camera batteries, drone batteries, and power banks -- up to roughly 20 spares, with the same 150 Wh-range approval requirement for larger batteries. The practical takeaway from these carrier-specific differences: checking the operating airline's own current battery policy before a trip involving multiple spare batteries or drone equipment is worth doing directly, since it can be genuinely stricter than the federal minimum.

A Recent Event Driving Newer, Stricter Rules

Beyond the baseline TSA/FAA rules, it's worth knowing about a specific 2025 incident that pushed several airlines toward genuinely stricter power-bank policies. On January 28, 2025, an Air Busan aircraft caught fire while preparing for takeoff at Gimhae International Airport in South Korea, injuring seven people and forcing an evacuation of all 176 passengers and crew via inflatable slides -- investigators identified a power bank as a likely source. In direct response, South Korea implemented nationwide rules banning power banks from overhead bins entirely on all of the country's airlines (they must instead stay in a seat pocket or under the seat, with terminals covered by tape or a protective pouch), and banning in-flight charging of power banks through a seat's USB outlet altogether. The restriction spread beyond South Korea -- Thai Airways and Singapore Airlines both introduced their own bans on charging power banks during flight in the months that followed. This recent example is worth knowing because it shows the rules in this space are still actively tightening in response to documented incidents, not settled permanently at today's federal baseline -- checking the specific operating airline's current policy remains genuinely worthwhile even for a traveler who already knows the general TSA/FAA rules well.

What This Means for Packing a Trip

The practical takeaway is to sort electronics by the installed/spare distinction specifically, not just by device type: a laptop with its battery installed can go in a checked bag if truly necessary (though keeping it in carry-on remains the more cautious choice most airlines themselves recommend), while every spare battery and power bank, regardless of size, belongs in carry-on with its terminals protected. For any battery approaching or exceeding the 100 Wh threshold -- larger camera, drone, or specialized equipment batteries especially -- checking both the printed watt-hour rating and the specific operating airline's own current policy before departure avoids an avoidable problem at the checkpoint.