Fabricating Fine-Grained Copper Foil by Ultrafine Anode Scanning Electrodeposition without Using Additives

Copper foil, recognized for its excellent electrical conductivity, malleability, and corrosion resistance, is widely used in various applications, notably in lithium-ion batteries and printed circuit boards. However, decomposition products from organic additives often decrease its electrical performance. This study introduces ultrafine anode scanning electrodeposition (UAS-ECD), a new method that firms copper foils without organic additives. Increased scanning speed enhances the diffusion of copper ions and reduces concentration polarization but also loosens the deposition layer, decreasing the tensile strength and surface quality of the copper foil. Increased current density leads to decreased surface quality, finer grain size, and increased tensile strength. Experimental results indicate that utilizing the concentrated current density and the significant local overpotential characteristics of line anode ultrafine anode scanning electroplating can prepare high-purity copper foil, approximating the performance of high-performance electroplated copper without additives.