Researchers at the University of Eastern Finland (UEF) have discovered that replacing the graphite in lithium-ion batteries with electrochemically-produced nanoporous silicon will significantly increase the battery's energy storage capacity. According to a press release by the institution, the hesitancy with using nanoparticles and nanostructured silicon in batteries has been because of its comparable volumetric capacity (its internal energy storage capacity) to graphite, as well as high production cost. However, the research team at UEF has figured out how to utilize larger particles measuring between 10- and 20 micrometers—a significant discovery as these particles are both safer and cheaper to produce.
“We now have a good understanding of the material properties required in large-scale use of silicon in lithium-ion batteries," said Vesa-Pekka Lehto, a professor at the Department of Applied Physics at UEF, in the release. "However, the silicon we’ve been using is too expensive for commercial use, and that’s why we are now looking into the possibility of manufacturing a similar material from agricultural waste, for example from barley husk ash.”
As silicon is the second most abundant element found in the Earth's crust (the first being oxygen), this method could be a sustainable solution to expand the energy storage capacity of the widely-used lithium-ion battery. "The transition to emission-free energy forms in transportation requires specific solutions for energy storage, and lithium-ion batteries are considered to have the best potential," according to the same press release.