Life Cycle Assessment and Environmental Life Cycle costing of a unitised regenerative fuel cell stack.

Life Cycle Assessment (LCA) and Environmental Life Cycle Costing (eLCC) are useful methods for evaluating the environmental, energy and economic performances of innovative energy storage technologies. By using these methods, the production process of a small Polymer Electrolyte Membrane Unitized Regenerative Fuel Cell (PEM-URFC) stack has been investigated, aiming to assess its environmental, energy and economic impacts at the early design stage and to identify the contributions of its various components on these impacts. Indeed, the PEM-URFC stack includes Critical Raw Materials that affect the product's sustainability. Results show that the highest contributions are associated with the platinum group metals used for the catalyst and, to a lesser degree, the materials and energy used for the bipolar plates and porous transport layers. However, considering that the datasets for representing the impacts of one of the electrocatalysts (Iridium Ruthenium Oxide) are still missing in LCA commercial databases and literature, a sensitivity analysis is performed assuming its impact to be similar to that of other Platinum Group Metals (PGMs) extracted with them (e.g., Platinum, Nickel, Palladium, etc.). The analysis shows a high difference in results due to data and methodological assumptions, making the assimilation of Iridium Ruthenium Oxide to Rhodium the worst scenario, increasing environmental impacts by 37.54 %, energy impacts by 40.48 % and environmental price by 45.08 %. Moreover, the study identified issues for applying life cycle thinking approaches on URFC devices that must be resolved in future studies (e.g., increase the reliability of catalyst inventory data or improve guidelines on energy storage technologies).

Electrochemical Impedance Spectroscopy as a Diagnostic Tool in Polymer Electrolyte Membrane Electrolysis.

Membrane⁻electrode assemblies (MEAs) designed for a polymer electrolyte membrane (PEM) water electrolyser based on a short-side chain (SSC) perfluorosulfonic acid (PFSA) membrane, Aquivion®, and an advanced Ir-Ru oxide anode electro-catalyst, with various cathode and anode noble metal loadings, were investigated. Electrochemical impedance spectroscopy (EIS), in combination with performance and durability tests, provided useful information to identify rate-determining steps and to quantify the impact of the different phenomena on the electrolysis efficiency and stability characteristics as a function of the MEA properties. This technique appears to be a useful diagnostic tool to individuate different phenomena and to quantify their effect on the performance and degradation of PEM electrolysis cells.