Hybrid aqueous battery based on Na3V2(PO4)3/C cathode and zinc anode for potential large-scale energy storage

• A hybrid battery with Na3V2(PO4)3/C as cathode and Zn as anode is proposed.
• Energy density as high as 112 Wh kg−1 is achieved in aqueous sodium battery.
• The hybrid system demonstrates its potential for large-scale energy storage.

A hybrid aqueous rechargeable battery with Na3V2(PO4)3 as cathode and metal Zn as anode has been proposed. Na3V2(PO4)3 is co-incorporated by carbon and reduced graphene oxide. The battery delivers a capacity of 92 mAh g−1 at a current density of 50 mA g−1 with a high and flat operating voltage of 1.42 V. It exhibits a capacity of 60 mAh g−1 at a high current density of 2000 mA g−1, indicative of excellent rate capability. Such inexpensive and safe battery shows an energy density as high as 112 Wh kg−1, demonstrating that it is potential for future application in large-scale energy storage.