Effect of deposition temperature on mechanical properties of nanotwinned Cu fabricated by rotary electroplating

A rotary electroplating system was used to fabricate high-strength nanotwinned copper (nt-Cu) foils with slanted columnar grain structures, which may serve as the anode current collector in lithium ion batteries (LIBs). By controlling the temperature of electrolyte bath and current density during electroplating, it is possible to tune the nanotwinned microstructure to optimize mechanical properties of the electroplated nt-Cu foils. The ultimate tensile strength (UTS) of nt-Cu foils has been enhanced by 60% of the ordinary nt-Cu from 403 MPa to 637 MPa. We found that UTS of the electroplated nt-Cu foils increases with decreasing temperature of electrolyte bath. The tensile strength of the nt-Cu foils increases approximately by 10 MPa for 1 °C decrease in the electrolyte temperature. The highest UTS of 637 MPa was obtained in rotary-electroplated at 6 °C and a current density of 11 ASD.