A compacted lithium powder anode was used to improve the demerits of dendrite formation of lithium metal. Dendrite formation of lithium metal was restrained to use compacted lithium powder anode under a specific amount of discharge and the current density. In this study, the amount of discharge and the current density which suppress dendrite formation at the surface of a lithium powder electrode were investigated on an experimental basis. Discharge/charge reactions were accomplished on various values of the amount of discharge and current density by using beaker cells. It was analyzed by SEM images whether dendrite was formed or not on the surface of lithium powder electrode. From the various experiments, the relationship between current density and total amount of discharge was deduced as a simple mathematical model. From the model, the critical condition of total amount of discharge for dendrite formation in Li-powder electrode was increased from 0.1mAcm−2 to 1mAcm−2 current density. However, the critical condition of total amount of discharge was decreased over 1mAcm−2. Using the model, the condition whether dendrite formed or not on the Li-powder anode could be estimated.