New insights on the reaction mechanism and charge contribution of NaNiF3 perovskite as an anode for sodium-ion batteries

Sodium-ion battery is a growing technology that has become a major focus of attention for energy storage of smart electric grids and renewable energy because of the enormous availability of sodium and its low cost of production. Particularly, the perovskite structure is an attractive material due to its novel properties in energy applications, such as good ionic mobility, low cost, facile route of synthesis, and fabrication. In the present work, an electrode based on NaNiF3 nanostructured perovskite active materials was explored as an anode for sodium-ion battery application. The morphology and microstructure of NaNiF3 perovskite were optimized using trisodium citrate dehydrated and microwave heating. Here a remarkable first capacity of c.a. 376 mA h g(-1) of the optimized electrode was obtained in the first discharge. The ex-situ XRD and electrochemical characterization of the active material allow proposing a reaction mechanism by conversion processes during the discharge and identifying a capacitive contribution of around 25% to the total current at 20 mV s(-1).