Dendrite-induced short circuit and capacity loss present major barriers to high-energy-density lithium (Li) metal batteries. Many approaches have been proposed to regulate or restrain the formation of Li dendrite, yet it has not been fully eliminated. Herein, a dredging tactic with hemisphere-like concaves is designed to horizontally release the stress during Li deposition, making both upper smooth Li and nether granular Li dwell inside the compartmented tummy. With such protuberance-free Li metal anode, an ultrahigh Coulombic efficiency over 96% of the half-cell is maintained after 490 cycles and capacity retention of 100% for the full cell paired with a LiFePO4 cathode after 140 cycles (with low N/P ratio of ≈5) is achieved simultaneously. This study contributes to a deeper comprehension of electrochemical metal deposition and promotes the development of safe batteries.