Is the end of lithium-based batteries imminent? When batteries using this chemical element perform satisfactorily, it is rare and expensive. Also, the scientific community is exploring alternatives that would reduce costs while minimizing impact on the planet and people.
These alternatives include sodium-metal batteries. In fact, sodium is plentiful. Its operation could be more sustainable and even improve the performance of batteries.
But today sodium-metal batteries cannot yet replace lithium batteries due to a technical problem that prevents their commercialization.
Sodium has one major downside
That problem is the dendrites, expansive formations that appear when the battery is in use and that puncture the membrane separating the two electrodes. In this case, a short circuit may occur.
The good news is that researchers at the University of Bristol in the UK have announced they have found a way to use sodium-metal batteries without the risk of puncturing that membrane. In collaboration with Imperial College and University College London, they have developed a new separator based on brown algae that prevents the penetration of sodium crystals.
“We have shown that algae-based materials can make the separator very tough and prevent it from being punctured by metallic sodium structures.”explains Jing Wang, one of the authors of the scientific publication.
A battery that lasts longer
And not only does this battery allow the use of a lithium alternative, it would also have better storage capacity and longer lifespan. According to a New Atlas article, the team tested this new algae-based battery and the results were “unprecedented.” Aside from having no problems with the separator, the battery retained a high energy density after 1,000 cycles (charge/discharge) despite the use of sodium.
Now the team behind this discovery is investigating production and also plans to apply the same technique to other types of batteries. For Amaka Onyianta, creator of the algae-based material, it’s already a victory for the planet.
“[…] We would not have to rely on rare materials like lithium, which is often unethically mined and uses large amounts of natural resources like water to mine.”She said.