Lithium-ion batteries can be divided into hard-packed and soft-packed batteries according to different electrolyte forms. Hard-packaged lithium-ion batteries are often packed in steel and aluminum shells. The steel shells are gradually replaced by aluminum shells due to their heavy weight and poor safety; The soft pack battery is also called "polymer battery", and the polymer lithium ion battery outer package is made of aluminum plastic packaging film. The soft pack battery using the aluminum-plastic packaging film has multiple advantages, such as high safety, variable shape and arbitrary shape, and can be made thinner. The average thin aluminum battery can only be 4mm, the softest lithium-ion battery can be 0.5mm, and the flexible packaging can save more than 20%. Soft packs are being widely used in the process of replacing aluminum shells. At present, in the smart phones, tablets, wearable devices, soft pack batteries account for the majority, the mainstream electric cars also use a soft pack of lithium-ion battery system. The world-famous Nissan LEAF and GM VOLT are all technical routes using soft-pack batteries. The quality of aluminum-plastic packaging film for batteries is extremely high, such as high barrier properties, good cold stamping formability, puncture resistance, electrolyte stability and heat resistance. Due to the high technical barriers, China's aluminum-plastic packaging film is highly dependent on imports. The domestic aluminum-plastic packaging film is basically monopolized by Japanese companies such as Showa Denko and DNP, and its market share reaches 90%. At present, some of the leading technology companies in China have made technological breakthroughs. It is expected to gradually achieve import substitution by localization and cost advantages. The next 2-3 years will be the most critical time for the localization of aluminum-plastic packaging film. Domestic enterprises with solid technical foundation, mature product research and development programs, and customer base are expected to become the main force in domestic substitution. Dongguan Aluminum's self-developed aluminum-plastic packaging film products have begun to be introduced to the market, and plans to gradually enter the well-known battery manufacturer supplier system in the future. At present, some domestic enterprises are in the process of certification of international first-line lithium-ion battery customers, and some enterprises are actively engaged in technical cooperation with international enterprises. From the history of the development of other materials for lithium-ion batteries, the localization replacement space for aluminum-plastic packaging films is very large.