Synthesis and Electrochemical Performance of Sodium Iron Phosphate Cathode Battery Based on Water-Chitosan Slurry

Abstract

The implementation of water-chitosan slurry is needed to achieve better battery, in terms of enviromentally friendly and cheapest cost. In this research, sodium-ion cathode batteries based on sodium iron phosphate and the water-chitosan slurry were successfully synthesized with the sol-gel method. The result of the X-Ray Diffraction (XRD) test confirmed the two phases of sodium iron phosphate, which are Na3Fe2(PO4)3 and Na3Fe3(PO4)4, with the percentage weight of the phases of 31.19% and 68.81%, respectively. Then, this sample was examined using Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX) test, it is known that the morphology of particles look like agglomerate thin sponges and no other elements besides Na, Fe, P, and O were found in the sample. Cyclic Voltammetry (CV) dan Electrical Impedance Spectroscopy (EIS) tests were also carried out to determine the electrochemical performance of the cathode material. The CV test was carried out to determine the specific capacity value of each sample. From the test results, it is known that sodium iron phosphate cathode with PVDF binder had a higher specific capacity value than cathode with chitosan binder, which was 44.13 mAh/g and 26.78 mAh/g, respectively. From the EIS results, it was found that sodium iron phosphate cathode with chitosan binder had better electrical conductivity and Na+ ion diffusion, with values of 7.44×10-3 S.cm-1 and 1.48×10-11 cm2 s-1 respectively.