Scalable Sustainable Anodes for Li-ion Batteries by Structural Design - SUSTBATT
This project has been highly successful in establishing new scientific and technological foundations for the use of biologically derived silica in energy storage applications. Our work demonstrated, for the first time, that industrially cultivated diatom microalgae can be effectively employed as a renewable template for the synthesis of nanostructured silicon suboxide (SiOx) materials, which are promising negative electrodes for lithium-ion batteries (LIBs). This concept—linking large-scale diatom culturing with advanced materials for energy storage—was both novel and impactful, as proven by the excellent scientific outcomes achieved during the course of the project.
We showed that diatom frustules (the intricate silica shells of diatom microalgae) retain their hierarchical nanostructure after undergoing magnesiothermic reduction (MgTR)—a solid-state chemical transformation that converts SiO₂ into SiOx/Si composites. By optimizing this reaction pathway, we obtained functional anode materials with high capacity and improved cycling stability.
To date, the project has already resulted in five scientific publications in high-impact peer-reviewed journals, highlighting the significance and scientific rigor of our findings. These publications span from fundamental characterization of the reduction process and material structure to detailed electrochemical analysis in half-cell configurations, confirming the applicability of our materials in real-world battery systems.
In addition to the scientific contributions, the project provided concrete proof-of-concept that the supply of microalgae-based SiO₂ is scalable and reproducible, thanks to our collaboration with an industrial partner dedicated to large-scale diatom cultivation. This ensured that our approach is not limited to lab-scale feasibility, but can realistically be extended to industrial production pipelines.
Importantly, the project also paved the way for future innovation. While the initial goal of demonstrating functional nanostructured SiOx anodes from diatoms was fully achieved, we also identified key challenges related to upscaling the magnesiothermic reduction reaction and slurry preparation, which required optimization stages.
Overall, this project has proven that bio-derived, structurally defined silica materials can serve as a foundation for highperformance battery electrodes and that this approach holds immense potential for sustainable battery material production.
