▎ 摘　　要

NOVELTY - Sodium metal battery comprises a anode pole piece and a negative pole piece, where the negative pole piece is a negative pole current collector. The thickness of the sodium layer deposited on the original position of the negative pole current collector is not less than 30 nm after the battery is charged and discharged for the first time. USE - Used as sodium metal battery. ADVANTAGE - The battery: utilizes the first irreversible capacity of anode electrode material and optimization of the design of the battery core; avoids the high nucleation energy required by sodium deposition to the surface of the current collector in the subsequent charging and discharging cycle process; reduces the overall deposition; and ensure the deposition uniformity of sodium metal and reversibility of charging and discharging process. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a electrochemical device.