Portable power banks can be a travel lifesaver, keeping your devices charged through a long day of sightseeing. But the rules around flying with such batteries have recently gotten a bit more complicated.

It’s long been the case that lithium-ion batteries aren’t allowed in checked luggage because they can be a fire hazard. Recently, Southwest Airlines started requiring that portable chargers stay visible while in use, so you can’t charge your phone or laptop in the seatback pocket or overhead bin. Emirates forbade the use of power banks on board, or storage of them in an overhead bin; several Asian airlines and countries have enacted similar restrictions.

If you fly with a portable battery, know your airline’s policy before you get to the airport, to save yourself the headache of repacking at the check-in desk or gate, or running out of power midflight. Click to the articles below for other items that should be on your pre-trip checklist.