Mobile power pack (MPP), also known as power bank, travel charger, etc., is a portable charger integrating power supply and charging functions, which can charge mobile phones, tablet computers and other digital devices. Generally, lithium battery cell is used as the energy storage unit, which is convenient and fast to use.

According to the notice on strengthening the safety management of general aviation short haul passengers carrying lithium batteries on board issued by the Civil Aviation Administration of China, lithium batteries are contained in mobile phones, power banks, computers, cameras, tablets and other electronic devices carried by short haul passengers on board, which are prone to smoke and fire caused by internal short circuit of lithium batteries in the event of collision, extrusion, high temperature and other situations during flight. In order to ensure the quality and safety of mobile power supply, mobile power supply needs to be tested and identified by an authoritative third-party testing and certification organization before entering the market.