A High-Power Na_3V_2(PO_4)_3-Bi Sodium-Ion Full Battery in a Wide Temperature Range

摘要

Sodium-ion batteries (SIBs) that operate in a wide temperature range are in high demand for practical large-scale electric energy storage. Herein, a novel full SIB is composed of a bulk Bi anode, a Na3V2(PO4)(3)/carbon nanotubes composite (NVP-CNTs) cathode and a NaPF6-diglyme electrolyte. The Bi anode gradually evolves into a porous network in the ether-based electrolyte during initial cycles, and in the NVP-CNTs cathode the NVP is cross linked by CNTs to show large exchange current density. These unique features merit the full SIB of Bi//NVP-CNTs with high Na+ diffusion coefficient and low reaction activation energy, and hence fast Na+ transport and facile redox reaction kinetics. The resultant full SIB presents high power density of 2354.6 W kg(-1) and energy density of 150 Wh kg(-1) and superior cycling stability in a wide temperature range from -15 to 45 degrees C. This will shed light on battery design, and promote their development for practical applications in various weather conditions.