Cost advantages and performance advantages drive the rapid development of the composite foil market

Composite foil is a new type of power battery current collector material. Usually the middle layer is a plastic film made of PET/PEN/PP and other materials, and there is a layer of 1-2μm thick aluminum or copper and other metal materials on both sides. Compared with traditional foil , composite foil has four advantages: First, high safety. The composite foil has a conductive film with a flame-retardant structure in the middle. When there is a short circuit in the battery, the short-circuit current can be cut off by fusing, effectively preventing the battery from heating up. Out of control; secondly, high specific energy. Since the middle layer of the composite foil is made of plastic, it can effectively reduce the weight of the overall current collector material, thereby increasing the energy density; thirdly, long life, the plastic expansion coefficient in the composite material is small, and can Maintaining the integrity of the pole piece interface for a long time can extend the service life; fourthly, the composite foil also saves raw material costs to a certain extent by replacing the middle metal layer with a plastic layer.

In recent years, with the continuous development of new energy vehicles and energy storage markets, the demand for lithium batteries has grown rapidly. In 2021, the global installed capacity of power batteries will be 297GWh, a year-on-year increase of 94.68%. This provides a good demand market for the development of the composite foil market .

Composite foil materials can be divided into composite copper foil and composite aluminum foil according to their materials. Composite copper foil is mainly used in lithium iron phosphate batteries, and composite aluminum foil is mainly used in high-nickel ternary system batteries. For high-nickel ternary systems, the demand for improved safety is more urgent, and composite aluminum foil is expected to replace traditional aluminum foil; for price-sensitive iron-lithium batteries, composite copper foil can significantly reduce costs; for other ternary systems such as medium-nickel ternary Materials, for the purpose of reducing costs or improving safety performance, composite foils will also be used in part.

The released“China Composite Foil Industry Market Monitoring and Future Development Prospects Research Report 2022-2026” pointed out that composite foil The rapid development of the market has attracted a large number of companies to actively deploy. Currently, there are four main types of companies deploying in this field: one is the company that extends the base film factory to make composite foil, the other is the traditional foil factory, and the third is the panel with PVD accumulation. manufacturers, PCB manufacturers, etc., and the fourth is battery manufacturers. Among battery manufacturers, CATL’s composite current collector layout is in a relatively leading position, and Chongqing Jinmei New Materials, in which the company has a stake, has achieved mass production of composite foils. In addition, leading battery companies such as Guoxuan Hi-Tech, BYD, Yiwei Lithium Energy, and China New Aviation have also reserved a large number of composite current collector patents.

Investment analysts pointed out that compared with traditional foils, composite foils not only have performance advantages, but also cost advantages. Advantages, it has a large space to replace traditional foils in the battery field. In the future, as my country’s new energy battery market continues to develop and market competition intensifies, the need to reduce costs and improve safety will become more urgent. It is expected that the composite foil market will remain Rapid growth trend.