For years, scientists have considered sodium-ion batteries a safer and lower-cost candidate for large-scale energy storage than lithium-ion.
But so far, sodium-ion batteries have not operated at high capacity for long-term use. Lithium and sodium have similar properties in many ways, but sodium ions are much larger than lithium ions. This size difference leads to the rapid deterioration of a key battery component.
Meilin Liu, Chenghao Yang and colleagues wanted to find an anode material that would give sodium-ion batteries a longer life.
The researchers developed a simple approach to making a high-performance anode material by binding an antimony-based mineral onto sulfur-doped graphene sheets.
Incorporating the anode into a sodium-ion battery allowed it to perform at 83 percent capacity over 900 cycles. The researchers say this is the best reported performance for a sodium-ion battery with an antimony-based anode material.
To ultimately commercialize their technology, they would need to scale up battery fabrication while maintaining its high performance.