Synthesis and electrochemical characterization of novel high capacity Si 3− xFe xN 4 anode for rechargeable lithium batteries

Abstract

An innovative Si 3− x Fe x N 4 compound has been identified as possible anode for rechargeable lithium batteries. The compound was synthesized (ceramic method), characterized (PXRD, SEM), and evaluated for electrochemical performance behavior (charge–discharge).The Si 3− x Fe x N 4 anode exhibited higher specific capacity (470 mA h/g) and an acceptable capacity fade (<20%) upon extended cycling. The coulumbic efficiency of the compound was found to be 99% even after 50 cycles. The lower average oxidation number and the higher ionic radius of Fe dopant were believed to restrict the formation of passivating surface film and reduced the capacity fade of Si 3− x Fe x N 4 anode upon cycling.