Characterization of Na-based phosphate as electrode materials for electrochemical cells

Abstract We report the electrochemical properties of submicron-sized particles of NaFePO 4 . Two materials have been studied and characterized by XRD, SEM, EDX, EIS and Raman experiments: the maricite phase synthesized by hydrothermal method and the olivine phase obtained from delithiation of LiFePO 4 . NaFePO 4 materials have an electrochemical activity in Na cell using NaPF 6 –EC–DEC electrolyte, but only in the heterosite phase, and the capacity is reduced already in the second cycle. The two-phase system at intermediate compositions has also been analyzed.