The Synthesis Effects on the Performance of P2-Na0.6Li0.27Mn0.73O2 Cathode Material for Sodium-Ion Batteries

Abstract

Sodium-layered oxides are a promising category of cathodes for sodium-ion batteries with high energy densities. The solid-state method is the typical approach to synthesizing these oxides because of its simple procedure and low cost. Although the reaction conditions have usually been understated, the effect of reagents has often been overlooked. Thus, fundamental insight into the chemical reagents is required to perform well. Here we report in situ structural and electrochemical methods of studying the effect of using different reagents. The materials have a composite structure containing layered NaMnO₂ and Li₂MnO₃ components, where oxygen anionic redox can be triggered at high voltage by forming Na–O–Li configurations. The samples synthesized via MnCO₃-based precursors form the Li₂MnO₃ phase at evaluated temperature and perform better than those through MnO₂-based precursors. This work demonstrates that the reagents also impact the structure and performance of sodium-layered oxides, which provides new insight into developing high-energy cathode material.