Sodium iron phosphate (often formatted as NaFePO₄ or complex variants like sodium iron phosphate pyrophosphate, Na₄Fe₃(PO₄)₂P₂O₇) is an emerging, sustainable inorganic cathode material used primarily in next-generation sodium-ion batteries. It serves as an abundant, low-cost, and safer alternative to traditional lithium and cobalt-based battery chemistries