Long Cycle Life and High-Rate Sodium Metal Batteries Enabled by Regulating 3D Frameworks with Artificial Solid-State Interphases

The major challenge for sodium metal anodes is Na dendrite growth owing to the unstable and fragile solid-electrolyte interphase (SEI), leading to terrible cycle life and safety hazards. Constructing a robust SEI around a 3D porous host is considered to be a facile and efficient approach to stabilize Na metal anodes. Here, a durable 3D porous SnCl4@Na-rGO metal anode is fabricated by the in situ chemical reaction of SnCl4-containing carbonate electrolyte with Na-rGO. Attributed to the robust SEI and the stereoscopic structure, the symmetric cells achieve a prolonged cycle life of 500 h without voltage fluctuation at 2 mA cm(-2) and 2 mAh cm(-2). Moreover, the Na3V2(PO4)(3)||SnCl4@Na-rGO full cell exhibits long-term cycle stability (>600 cycles) and remarkable capacity retention (>92%). The novel approach provides an efficacious strategy for the practical implementation of Na metal batteries.

Automated summary

Constructing a robust solid-electrolyte interphase (SEI) and a stereostructure of a porous host is an effective approach to stabilize the performance of sodium metal anodes. The in situ chemical reaction between SnCl4-containing carbonate electrolyte and Na-rGO leads to the fabrication of a durable SnCl4@Na-rGO metal anode, which exhibits excellent cycle life and capacity retention under high rates and long cycles.