The broader/commercial impact of this Small Business Innovation Research Phase II project lies in addressing key challenges hindering widespread adoption of hydrogen fuel cells: their high cost due to expensive platinum catalysts, and their limited operational lifespan. The primary expense in fuel cells comes from the use of platinum catalysts, which are both costly and subject to degradation over time. This project introduces an innovative process that renews these catalysts directly within assembled fuel cells, eliminating the need for disassembly. By enabling in-situ catalyst renewal, the technology is expected to extend the operational lifetime of fuel cells from 150,000 miles to 1.2 million miles, while also cutting total ownership costs in half. This advancement not only positions the United States as a leader in the hydrogen economy but also strengthens national security by varying energy sources, enhancing energy resilience, and creating employment opportunities. This project addresses a critical challenge in extending hydrogen fuel cell lifespan by pioneering a high-risk, in-situ electrocatalyst renewal process that circumvents stack disassembly. It will control catalyst transfer within assembled fuel cell electrodes quickly and at room temperature such that it results in a like-new platinum distribution at the electrode surface; a feat not previously achieved in the field. A range of advanced techniques will be employed to study platinum movement within fuel ce