A Study on Na1.2Mn0.8O1.5F0.5 Na-Rich Cathode Material for High Capacity and Superior Stability Sodium Solid-State Battery

Abstract

Sodium ion batteries are considered as a cost-effective and promising alternative to lithium-ion batteries for next generation large-scale energy storage applications. However, the sluggish intercalation kinetics and poor stability plagues the efficient applications. Recently, sodium rich cathode materials are emerging as a promising system to retain high specific energy with improved durability. Benefitting from the high Na ion mobility by P2-type structure and reduced John-Teller active Mn site, improved stability has been achieved for this Na-rich cathode. In this work, we developed a high performing Na rich cathode with Sodium Manganese Oxyfluoride (Na1.2Mn0.8O1.5F0.5 ) as a battery positive electrode. The corresponding structural and electrochemical performances are analysed in solid-state battery. The highly favourable cathode architecture demonstrated a high specific capacity of 178 mAh/g at 10 mA/g in half-cell configuration. To further harness its performance, the cathode material was coupled with solid-electrolyte and interface modified anode. Solid-state battery demonstrated an enhanced capability towards ion storage and better stability.