Copper Polypropylene Metal Plastic Composite Copper Foil: Future-Proof Anode Current Collector Solution for Lithium-Ion Batteries with High Energy Density

Composite copper foil is considered to be the future-proof anode current collector solution for lithium-ion batteries (LIBs) with high energy density, for its light weight and low cost. Polypropylene (PP) film is widely used as the support layer of composite copper foil current collectors (CCs) due to its excellent mechanical properties and chemical stability. However, the interface adhesion between the PP layer and the copper layer is weak, due to the significant difference in surface energy. In this study, we prepared a hydrophilic PP film by air plasma treatment. After magnetron sputtering and electroplating, the composite copper foil (PP@Cu-1) with strong adhesion was then successfully prepared. In the T-peel test, for PP@Cu-1, the pull required to separate PP from the copper layer is approximately 7 times that of PP@Cu-0. The PP@Cu-1 composite copper foil exhibits excellent electrochemical properties when applied to LIBs. As an anode CC material, it could be a favorable competitor to conventional commercial Bare Cu and holds broad prospects for application in high-energy-density LIBs.