Policies on portable power suppliers vary between airlines, so make sure to check your chosen carrier’s guidelines. As a general rule, you are allowed to take lithium batteries up to 100Wh on most planes. Batteries up to 160Wh will need special airline clearance, and above that is a no-go. The ChargeTech Portable AC Power Supply at number 9 is the only battery on this list suitable for airplane travel. Lithium batteries must be carried in your hand luggage, not stored in the hold.