Sodium (Na) metal is a critically encouraging anode material for next-generation rechargeable batteries own to its high specific capacity, earth-abundance and low-cost. However, the application of Na metal anode (SMA) is hampered by dendritic and “dead” Na formation caused by the uncontrolled Na deposition behavior, leading to poor cycle life and even safety concerns. Herein, a high-performance Na anode is designed by introducing an artificial VN interlayer on Na metal surface (Na/VN) by a simple mechanical rolling process to regulate Na nucleation/deposition behavior. The density functional theory (DFT) and experiments results uncover that the VN possesses high “sodiophilicity”, which can facilitate the initially homogeneous Na nucleation and endow Na to distribute evenly on the VN interlayer. Therefore, uniform Na deposition without dendrite-free morphology and prolonged cycling lifespan (over 1060 h at 0.5 mA cm-2/1 mAh cm-2) can be realized. Moreover, full cell assembled by coupling of Na3V2(PO4)3 (NVP) cathode and Na/VN anode presents superior cycling performance (e.g., 93% capacity retention even after 1000 cycles at 5 C). This work provides a promising direction for regulating Na nucleation and deposition to achieve dendrite-free metal anodes.
You have access to this article