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NASICON Na₃V₂(PO₄)₃ and Na₃V₂(PO₄)₂F₃ have restarted to be investigated electrochemically as promising cathode materials for sodium-ion batteries. Fluorine insertion by replacing partial phosphate groups in Na₃V₂(PO₄)₃ allows for new family of host lattice structure, Na₃V₂(PO₄)₂F₃. Greatly, fluorine is capable to participate in structural construction to change the ions configuration which involves ions occupation, the species and amount of diverse Na sites, leading to distinct modalities for ions extraction. The inductive effects of (PO₄)³⁻ polyanion by changing electronic cloud density upon compositional atoms could be enhanced under the effects of the formed F-V bond due to its strong ionicity, which can moderate the energetics of the transition metal redox couple to generate relatively high operating potentials. The substitution of fluorine for negative-charge polyanion or anion could be effective to …