Sodium Power That Works From Frost to Heat

Scientists have discovered that reconfiguring the tiny molecules of ether solvents can keep sodium metal batteries reliable from -40 °C to 70 °C.

The Problem

Standard weakly solvating ethers are too volatile, making them unsafe at high temperatures. Their low boiling points limit the operational range of sodium batteries.

The Solution

By reshaping ether molecules, researchers strengthened the bonds between solvent molecules themselves. This change:

• Raises boiling points
• Keeps solvation power low

The result is that sodium ions can leave their solvent shells more easily, even in cold air.

Performance Gains

• Stable output: At least 0.5 mA cm⁻² without losing capacity across a wide temperature band.
• Lab tests: Showed that the key to improvement lies not only in ion–solvent interactions but also in intermolecular forces among solvent molecules.
• When these forces are tuned correctly, the energy required for ion desolvation drops sharply at low temperatures.

Implications

The study suggests a simple route: tweak the solvent’s internal interactions instead of searching for entirely new chemistries. This approach could make sodium batteries:

• Safer
• More versatile for extreme‑weather gear
• Suitable for deep‑sea probes
• Reliable for spacecraft power supplies