SYNTHESIS AND CHARACTERIZATION OF Na0.67Mn0.65Fe0.20Ni0.15O2 AS CATHODE MATERIAL FOR SODIUM ION BATTERIES

Abstract

The major contribution to the battery performance is due to the cathode material. Stable sodium ion storage cathodes with adequate reversible capacity are now greatly needed for enabling Sodium-ion battery technology for large scale and low cost electric storage applications. The deintercalation and intercalation of sodium in various layered NaxMO2 has been reported for a very wide variety of transition metals as briefly outlined in a recent report[5]. The manganese and cobalt oxides are the most viable for positive electrodes. But cobalt is toxic and expensive. The Jahn-Teller distortion of Mn(III) is the most prominent factor which decides the structural stability for Mn-based oxides during ion insertion. Hence a general strategy applied to sodium based layered oxides is to substitute partial metal ions in the transition metal layer using selective cations, to improve the structural stability and electrochemical performances of the layered cathode host. In light of the better Lithium-ion storage performance of layered oxides, sodium based Na0.67Mn0.65Fe0.20Ni0.15O2, cathode material was synthesized by sol-gel method using citric acid as chelating agent. Synthesized Na0.67Mn0.65Fe0.20Ni0.15O2 has been characterized by X-ray diffractometer (XRD) to confirm the proper phase formation. Scanning Electron Microscope (SEM) for structural and morphological studies. The XRD measurement demonstrated that the sample have a pure P2 phase.