Lithium-sulfur batteries weigh less for the same amount of energy, compared to lithium-ion. This has great potential for electric vehicles, as it could increase driving range. However, the sulfur version has issues that prevent its early adoption. This could change though, after Washington State University announced that corn boosts lithium-sulfur performance. That’s the same flaky corn in a popular breakfast cereal.
A Novel Corn Separator in a Lithium-Sulfur Battery
Lithium-sulfur batteries use rechargeable cells, comprising lithium-based anodes, and sulfur-based cathodes. They have high energy storage density, due the low atomic weight of lithium, and moderate atomic weight of sulfur.
Lithium-sulfur batteries have two issues currently preventing their adoption as lithium-ion battery competitors:
- The sulfur material tends to leak into the liquid electrolyte, and move across into the lithium material.
- The lithium material on the far side often develops spiky dendrite growths, that can short circuit the two materials.
- Leaking sulfur weakens the battery, causing it to stop working after a short while. The spiky dendrites may cause instant lithium-sulfur battery failure.
The Washington State University scientists developed a protective barrier comprising corn protein, and a common polypropylene material. They claim this “significantly improves the performance of a button-sized lithium-sulfur battery”. Their prototype apparently still held full power after 500 recharging cycles.
Therefore, it seems likely that the novel separator prevented the sulfur material leaking into the liquid electrolyte. While at the same time, the separator prevented the sulfur and lithium short circuiting, via the spiky dendrites.
This, presumably, is how the corn boosts lithium-sulfur battery performance, as illustrated in their button-sized prototype. You’ll find more technical detail in their research report we link to below.
“Corn protein would make for a good battery material, because of it’s abundant, natural, and sustainable properties,” observes Jin Liu, professor in the School of Mechanical and Materials Engineering.
More Information
Lithium-Sulfur Battery Range Extender
Healing Lithium-Sulfur Batteries With Iodine
Preview Image: Prototype Lithium-Sulfur Battery
