This article summarizes the findings of this fruitful collaboration, published in the prestigious Journal of The Electrochemical Society, detailing for the first time the pilot-scale manufacturing and testing of lithium-ion pouch cells based on Iron Sulfide (FeS).
Sustainable and Scalable Manufacturing: The Key to the Process
One of the cornerstones of battery innovation is minimizing environmental impact. Therefore, the joint effort of CIDETEC and RIMSA focused on using a water-based slurry for the production of FeS electrodes. This approach eliminates the use of harsh organic solvents like NMP (N-methyl-2-pyrrolidone), aligning the manufacturing process with the new industrial adoptions following the principles of green chemistry.
Crucially, a water-based process is compatible with existing industrial infrastructure for anode production, a key factor in de-risking the future adoption of new materials like FeS.
This work has successfully bridged the gap between fundamental research and industrial application. Through this collaboration, a formulation with a high active material content (90% FeS) has been transferred from a laboratory mixer to a semi-industrial roll-to-roll coating line. The produced electrodes were then used to assemble multi-layer pouch cells, a commercially relevant battery format.
This achievement marks a milestone in the evaluation of FeS, not just as a material concept, but as a manufacturable component for next-generation energy storage.
The testing of the pouch cells provided crucial insights into the material’s behavior and defined a clear roadmap for future research and development phases. Its conversion mechanism for the storage of lithium is responsible for the complex chemistry of the lithiation-delithiation process and the parasitic reactions that may occur depending on the chemical nature of the other battery components and the cycling conditions.
FeS + 2Li+ + 2e− → Fe + Li2S
These findings are not setbacks, but essential data points that chart a clear path for material and cell optimization. Addressing sulfur shuttling and improving thermal stability are now the primary research objectives.
Although graphite remains the benchmark anode material in many applications, the unique properties of FeS, open up new possibilities in specialized markets where its profile offers distinct advantages.
The high crystallographic density of FeS presents a very interesting opportunity for applications where high volumetric energy density is a critical parameter. This means more energy can be stored in a limited space although it has to be confirmed that the reduction of the porosity of these anodes does not compromise the electrochemical performance of the cells. Some potential applications are:
This work, a result of the collaboration between CIDETEC and RIMSA (Innovamat) and built upon the advances of the LION-HD project, demonstrates the feasibility of industrially manufacturing FeS anodes using a sustainable, water-based process. By identifying the key challenges and potential high-value applications, we have established a solid foundation for the continued development of this promising material. This strategic alliance remains firm in its goal of advancing this technology, focusing on specific improvements to unlock its full potential in the next generation of energy storage solutions.
