Travel Tech

Travel electronics are the one category on this site where a published number is not just useful but legally binding. Every airline in the world caps the lithium batteries you may carry, and the cap is expressed in watt-hours — a figure most product listings bury and most buyers have never looked for.

The threshold is 100 Wh. Under it, a battery travels in your carry-on with no paperwork. Between 100 and 160 Wh you need the airline’s approval. Above 160 Wh it does not fly at all. A typical 10,000 mAh power bank is around 37 Wh, so it is nowhere near the limit — but a large laptop battery bank can be, and the number is printed on the case precisely because someone will eventually ask to see it.

What this section scores

• Watt-hours against the airline limit. Every power bank here states its published Wh, not just its milliamp-hours, because Wh is the figure the rule is written in. The full battery rules.
• Battery life against flight length. A headphone rated for 30 h covers any single flight on earth. One rated for 50 h covers a multi-leg trip without a charger. Beyond that the number stops mattering.
• Weight, as always. A tech pouch, a power bank and a pair of over-ear headphones total well over a pound between them, and none of it does much work per ounce.
• Warranty, where anyone publishes one. This is the weakest category on the site for published terms — the range runs from eighteen months to three years to nothing at all.

The rule that runs backwards

Almost everything you own is allowed in a checked bag and restricted in the cabin. Batteries are the opposite: spare lithium cells and power banks must travel in the cabin, where a fire can be seen and reached, and are prohibited in the hold.

That matters more than it used to, because gate-checking a carry-on is now routine on full flights. If your bag can be taken from you at the door, the power bank cannot be inside it. Keep the whole electrical kit in the bag that never leaves your hand, which is the single most useful habit in this section.

Where to start

If you are buying one thing, buy the power bank — it is the item whose absence you notice at hour six of a delay. The ranking is here. If you fly long-haul more than twice a year, the headphone comparison is the page that matters, and it is built around battery life rather than sound quality, because sound quality is not something we can assess and battery life is published.

And if your cables live loose in the bottom of a bag, a pouch is the cheapest fix in travel — the published weight range across the two we track is 0.24 lb to 1.2 lb, which is a fivefold difference for the same job.