Smart bags are those items of luggage that contain a li-ion battery: the battery power means that they may be fitted with USB ports or contain self-weighing technology or have small motors designed to power the luggage's wheels for ease of transport.
Southwest now joins Delta, Alaska Airlines and American in refusing the carriage in the hold of bags from which the batteries cannot be extracted. The bags may, however, be transported in the cabin (subject to size and capacity) or, where batteries are detachable, then these latter are permitted to be carried by the person on board. Simply put, anyone seeking to check in a smart bag with non-detachable li-ion batteries will be refused unless that bag can be accommodated in the cabin.
Recent tests have shown the dangers of thermal runway fire events where batteries are ignited in flight; in an inaccessible place like the hold, such dangers are not acceptable to a growing number of carriers.
