Researchers have developed a new solid-state sodium-ion battery that may offer a safer and cheaper alternative to conventional lithium-ion batteries used in electric vehicles (EVs) and large-scale energy storage, tells Live Science. The work, published in peer-reviewed journals Advanced Materials and Advanced Functional Materials, describes a battery with a solid electrolyte that replaces the flammable liquid electrolytes found in typical EV batteries. This change reduces the risk of thermal runaway, the process that can lead to fires or explosions when a battery cell is damaged or short-circuits, and boosts stability during charge and discharge cycles.
Lithium-ion batteries dominate today’s rechargeable market but carry safety and supply concerns. Their liquid electrolytes are volatile and can catch fire when heated or breached. Sodium-ion batteries, by contrast, use sodium ions, which have lower electrochemical energy and are less prone to dangerous overheating. Sodium is also far more abundant and less expensive than lithium, which could shrink material costs and ease supply chain pressures as demand for battery storage grows worldwide.
In the new design, researchers used a solid material containing sulfur and chlorine to conduct ions, achieving efficiencies on par with lithium-ion cells across hundreds of charging cycles. The solid-state electrolyte also supports high Coulombic efficiency, a measure of how much charge is retained each cycle, and hints at a feasible path to matching the performance of current batteries without the same safety trade-offs.
That said, sodium-ion batteries have historically lagged lithium-ion in energy density and lifespan. They don’t yet store as much energy per weight and can degrade faster, which limits driving range for EVs. The researchers emphasize the challenge ahead: scaling manufacturing while maintaining durability and capacity that meets commercial needs.
If those hurdles are cleared, this solid-state sodium-ion technology could make EVs and grid storage systems significantly safer and more cost-effective, accelerating adoption in both transportation and renewable energy sectors.