Life cycle assessment of manufacturing routes for protonic ceramic cells: a comparison of three fabrication routes

Reducing dependence on fossil fuels is one of today's most pressing topics, and hydrogen is a promising solution to support this transition. Proton-conducting ceramic cells (PCCs) are key in this context, producing and using hydrogen at lower temperatures than conventional ceramic cells. Understanding the environmental burden of their production is becoming as important as their electrochemical performance, yet Life Cycle Assessment (LCA) studies on PCC manufacturing remain scarce. For this reason, a collaboration between the UNIBO Research Group "Chemistry for the Environment and the Cultural Heritage" and CNR-ISSMC (Faenza, Italy) was established to compare manufacturing routes for protonic ceramic button cells through LCA. The routes considered are tape casting (Route A), tape casting with screen-printing (Route B), and freeze casting with screen-printing (Route C), compared for one cell unit. The inventory was built with CNR-ISSMC using primary laboratory data, and the LCA used the Environmental Footprint 3.1 method, identifying which routes and steps drive the impact most. Routes A and B perform very similarly, showing that screen-printing does not meaningfully increase the environmental burden. Route C instead shows a single score about 67% higher at the manufacturing stage, due to the structural nature of freeze casting, which requires more thermal treatments than the other routes. Electricity consumption is the main driver of impact across all routes, especially Climate change and Fossil Resource Depletion, driven by debonding and sintering for Routes A and B, and by calcination and sintering for Route C. Although less favorable in manufacturing, Route C could still be worthwhile if its process performance proves superior in technical terms. If its porous structure delivers longer-lasting performance, the higher burden could be justified over the cell's full life, a comparison to complete once future studies include the operational phase.