How does airport security verify that you can carry a battery bank …
It is not the case that the FAA bans all battery packs above 100 Wh. As their own link states, up to two batteries above 100 Wh and up to 160 Wh are permitted onboard, with airline approval. Sometimes the airline approval is just provided carte blanche; sometimes it''s provided with advance permission, as in your case.
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