Fast Charging Sodium‐Ion Full Cell Operated From −50 °C to 90 °C

Abstract The application of sodium‐ion batteries (SIBs) within grid‐scale energy storage systems (ESSs) critically hinges upon fast charging technology. However, challenges arise particularly with anodes such as hard carbon (HC), which exhibits a low working plateau (less than 0.1 V vs Na/Na⁺) and is susceptible to sodium dendrite issues under high current densities. In this study, a cost‐effective SIB system comprising Na_2.4Fe_1.8(SO₄)₃ (NFS) cathode, NaTi₂(PO₄)₃ (NTP) anode, and ester‐based electrolyte is assembled to solve the fast‐charging obstacle. Benefiting from the fast sodium‐ion diffusion kinetics and relatively high voltage platform of NTP anode, this full cell can work for 10 000 cycles at 10 C rate with a notable capacity retention of 70.7%. Moreover, this investigation reveals that the full cell can operate safely between ‐50 to 90 °C even with an ester‐based electrolyte, thereby showcasing broad application prospects. This work provides a valuable guidance for designing fast charging and wide temperature SIBs.