Amorphous iron vanadate (FeVO4) nanoparticle cathode materials are successfully synthesized through a facile, efficient, and high-yielding ion exchange-liquid precipitation method. The composition, structure, morphology, surface area, and electrochemical performances of the synthesized materials have been characterized by the Thermogravimetric-Differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photon spectroscopy (XPS), Brunauer-Emmet-Teller (BET), cyclic voltammetry (...