High crystalline Na2Ni[Fe(CN)6] particles for a high-stability and low-temperature sodium-ion batteries cathode.

Abstracts High crystalline Na 2 Ni[Fe(CN) 6 ] particles are synthesized by a new electrostatic spray assisted coprecipitation method. Their structures and electrochemical properties are analyzed by X-ray powder diffraction, scanning electron microscopy and galvanostatic cell cycling and so on. Given its highly stable structure, the optimized Na 2 Ni[Fe(CN) 6 ] cathode shows impressive cycling performance with high retention capacity of 89% after 440 cycles at 1 C and excellent rate capability of 56 mAh g−1 at 25 C. In addition, the optimized Na 2 Ni[Fe(CN) 6 ] cathode achieves superior low temperature performances with retains 87% capacity after 440 cycles at 0 °C and a stable capacity of 54 mAh g−1 can be delivered even at −25 °C after 440 cycles. Such a Na 2 Ni[Fe(CN) 6 ] sample provides a promising cathode for sodium-ion batteries in large-scale storage systems. Highlights • Highly crystalline Na 2 Ni[Fe(CN) 6 ] are prepared by a new ESAC method. • Na 2 Ni[Fe(CN) 6 ] shows superior electrochemical properties at different temperatures. • Na 2 Ni[Fe(CN) 6 ] will be a promising cathode for sodium-ion batteries. [ABSTRACT FROM AUTHOR]