A high-energy-density sodium-ion full battery based on tin anode

Sodium-ion batteries (SIBs) have been considered as promising candidates for large-scale energy storage, owing to the high abundance and low cost of sodium (Na) resources. However, the development of full SIB has been hindered by low energy density because of the sluggish kinetics of large Na+. Here, we report a full SIB with commercial tin (Sn) anode, cross-linked Na3V2(PO4)3/carbon nanotubes composites (NVP-CNT) cathode, and ether-based electrolyte. Sn is capable of delivering high reversible capacity via formation of Na15Sn4 and stable solid-electrolyte interface (SEI) in initial cycles. Meanwhile, the NASICON-type NVP enables ultrafast and stable Na+ intercalation/extraction, and the incorporation of CNT can improve its electrical conductivity. The assembled full SIB delivers high output voltage of ~3.2 V, high energy density of 253.4 W h kg−1 at 1600 W kg−1 based on total mass of both cathode and anode, and remarkable capacity retention of 96.1% after 180 cycles. These merit construction of high-energy full SIBs and will promote the development of SIBs.