Effect of pulse electrodeposition process on the microstructure and properties of electrolytic copper foil as anode current collectors

Abstract

Developing new pulsed electrodeposition process for preparing high-strength electroplated copper foil as anode current collector for lithium-ion batteries is a highly promising research direction. This study reveals that appropriate pulsed electrodeposition process parameters, such as electrolyte temperature, current density, duty cycle and additives, can significantly enhance the tensile strength and elongation of copper foil. Under the same conditions, the mechanical properties of copper foil prepared by adding bis-(3-sulfonpropyl)-disulfide (SPS) are the most significant improvement, the tensile strength of electroplated copper foil reaches 640 MPa, while it is only 450 MPa by direct current electrodeposition. The main reason for the improvement in mechanical properties is the significant increase in the number of twins and dislocations under the combined effect of pulsed deposition and SPS, as well as the noticeable reduction in the thickness of twin lamellae and grain size.