Sodium-Ion Battery with a Wide Operation-Temperature Range from -70 to 100 °C

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sodium-ion batteries (SIBs) are crucial for grid-scale energy storage but struggle in extreme temperatures.
• Developing all-weather SIBs with a wide operating temperature range remains a significant challenge.

Purpose of the Study:

• To develop and demonstrate a sodium-ion battery capable of operating efficiently across a wide temperature range, from extreme cold to high heat.
• To investigate novel electrode materials and electrolytes for enhanced low- and high-temperature performance in SIBs.

Main Methods:

• Fabrication of a carbon-coated Na4Fe3(PO4)2P2O7 (NFPP@C) cathode and a bismuth (Bi) anode.
• Utilized a diglyme-based electrolyte for improved thermal stability.
• Investigated the Na+ storage mechanism in the Bi anode and Na+ diffusion in the NFPP@C cathode across various temperatures.

Main Results:

• The Bi anode directly stores solvated Na+ via an alloying reaction without desolvation.
• The NFPP@C cathode demonstrates a high Na+ diffusion coefficient, even at low temperatures.
• The Bi//NFPP@C battery retained 70.19% of its room-temperature capacity at -70°C and operated effectively up to 100°C.

Conclusions:

• The developed Bi//NFPP@C SIB exhibits excellent performance across a wide temperature range (-70°C to 100°C).
• This research provides a promising pathway for the development of robust, all-weather SIBs for grid-scale energy storage applications.