Structural properties and electrochemical performance of the polyanionic Na 4 Fe 3 (PO 4 ) 2 (P 2 O 7 )@C cathode at lower cutoff potentials for sodium-ion batteries

over 300 cycles. Moreover, the cathode maintains its phase transitions, exhibiting uniform charge and discharge plateaus, low polarization, and low total resistance. Eventually, this study lays the groundwork for further research on the potential window of the NFPP@C cathode for sodium-ion batteries and the development of a mechanistic strategy.