Cathode material discovery boosts the drive for sodium-ion batteries
During the past five years, sodium-ion batteries have emerged as a promising new type of rechargeable battery and an alternative to lithium-ion batteries because sodium, better known as the main element of salt, is abundant and inexpensive. In contrast, lithium-ion batteries are limited by high production costs and availability of lithium.
Professor John Goodenough, the inventor of the lithium-ion battery, and his team have identified a new cathode material made of the non-toxic and inexpensive mineral eldfellite which could become key to the development a commercially viable sodium-ion battery. The researchers reported the findings in the journal Energy & nvironmental Science.
“At the core of this discovery is a basic structure for the material that we hope will encourage researchers to come up with better materials for the further development of sodium-ion batteries,” said Preetam Singh, a postdoctoral fellow and researcher in Goodenough’s lab.
Sodium-ion batteries work just like lithium-ion batteries. During the discharge, sodium ions travel from the anode to the cathode, while electrons pass to the cathode through an external circuit. The electrons can then be used to perform electrical work.
Although sodium-ion batteries hold potential, there are obstacles to advancing the technology including issues related to performance, weight and instability of materials. The team’s proposed cathode material addresses instability. The material’s structure consists of fixed sodium and iron layers that allow for sodium to be inserted and removed while retaining the integrity of the structure.
One challenge the team is currently working through is that their cathode would result in a battery that is less energy dense than today’s lithium-ion batteries. The UT Austin cathode achieved a specific capacity (the amount of charge it can accommodate per gram of material) that is only two-thirds of that of the lithium-ion battery.
“There are many more possibilities for this material, and we plan to continue our research,” said Singh. “We believe our cathode material provides a good baseline structure for the development of new materials that could eventually make the sodium-ion battery a commercial reality.”
Related articles and links:
News articles:
Graphene oxide discovery helps boost rechargeable batteries
Samsung partners MIT to create longer-lasting solid-state rechargeable batteries
Nanoparticle electrodes offer capacity boost for lithium-ion batteries