Unitized regenerative fuel cells: Fundamental challenges and advancements
Year: 2025
Type: article
Abstract: A unitized regenerative fuel cell (URFC) refers to a single cell that can operate as both an electrolyzer and a fuel cell. URFCs, therefore, could play a significant role in the shift to a sustainable energy future, decreasing the cost of implementing hydrogen technologies across applications from off-grid to distributed energy systems using renewables. However, to date, the high cost associated with the practical use of URFCs remains a significant barrier. Existing URFC stacks suffer from limited efficiency. Noble metals such as Pt, Ir , and Ru limit possible cost reduction and to date, only these noble metals can effectively catalyze the URFC reactions in a reversible way. Non-precious metal catalysts experience severe degradation and low intrinsic catalytic activity for both the hydrogen/air reaction in fuel cell mode and water splitting in electrolysis mode. This review provides a summary of the latest advancements in URFCs, highlighting areas for improvements and explores how separate state-of-the-art developments in electrolyzers and fuel cells could potentially enhance the efficiency of URFCs. The history and recent performance of URFC stacks, flooding and corrosion mechanisms , thermal and water management systems are discussed. Various optimization strategies for improving the performance of URFC components , such as the membrane, catalyst layer , bipolar plate , gas diffusion layer, and flow field designs, are also reviewed.
Authors: Asim Shahzad, Haihui Joy Jiang, Kondo-Francois Aguey-Zinsou
Institution: The University of Sydney
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,220
OpenAlex ID: W4408576463