Synthesis route and properties of sodium-ion batteries: the usage of sodium chloride on maricite-NaFePO₄

Abstract

Sodium iron phosphate (NaFePO4) is widely used for cathode in sodium-ion batteries (SIB). SIB is a type of secondary battery that employs sodium ion as it charge carriers during battery’s operation. Here we report the synthesis of NaFePO4 using sodium chloride (NaCl) as a source of sodium via sol-gel method and study of its properties. X-Ray diffraction (XRD) data show the existence of maricite NaFePO4 and the secondary phase, Na3Fe2(PO4)3. Scanning Electron Microscope (SEM) result indicates the fairly homogeneous long-oval shaped of the maricite particle with the size range of ∼2 μm. Electrochemical properties studied by electrochemical impedance spectroscopy (EIS) measurement obtain the ion diffusion coefficient of NaFePO4 is 7×10−14 cm2s−1 that is in line with other types of SIB.