Metallic Li was electroplated onto a Cu foil current collector in an anode-free Li-metal coin cell by constant-current and pulsed current formaFon protocols. It is shown that smoother deposits can be obtained by using an opFmised pulsed current protocol compared to constant-current protocols. Arer the complete formaFon cycle the obtained Coulombic efficiency of the opFmised pulsed current formaFon C/2 with on-Fme of 0.25 s and off-Fme of 0.75 s protocol is approx. 10% higher than that of the convenFonal C/20 constant-current formaFon protocol. This is likely due to the obtained smoother metallic Li deposits with lower surface area and therefore less acFve Li loss due to the passivaFon reacFon with the solvent. Moreover, the Fme necessary to complete the formaFon process is more than halved compared to the convenFonal, C/20 constant-current formaFon protocol. Furthermore, we show that reproducibility between the cells is poor, although on average the pulsed current formaFon protocol improves the Coulombic efficiency. This is confirmed using XGBoost regression, which shows very weak agreement between predicFons and test values if charge and discharge rate, and on and off-Fmes are used as input features. A strong agreement between predicFons and test values was achieved if pseudo-IR-drop was used as an input feature. Hence, the Coulombic efficiency of the formaFon process could be explained and potenFally predicted form pseudo-IR-drop by XGBoost regression Namely, the high IR-drop during pulsed charging is likely due to the formaFon of rough deposits and consequently the large surface area of the passivated Li, which has higher resistance than smooth Li deposits. In addiFon, we joined IR-drop with off-Fme into pseudo-IR-drop in order to find an opFmal off-Fme for metal ion replenishment. In this way, the pulsed current protocol could potenFally be tailored to each cell individually, with appropriate off-Fme and/or reverse pulse to discharge the dendrites.