Electro-Redox Oxygen Cycling v3: Design-Validated and Catalyst-Anchored Framework for Automotive-Scale Onboard Hydrogen Generation

This work presents version 3 of the Electro-Redox Oxygen Cycling (EROC) framework, a low-voltage onboard hydrogen generation system designed for automotive-scale applications. EROC replaces a significant fraction of the electrical energy required for water splitting with internally stored redox free energy in transition-metal oxyhydroxides, enabling stable hydrogen production in the 0.5–1.0 V regime. Building upon prior feasibility studies, this version introduces sensitivity-validated Monte Carlo analysis over wide electrochemical parameter ranges, explicit decomposition of total overpotential into activation, ohmic, and mass-transport contributions, and catalyst-anchored performance mapping using experimentally reported Ni–Fe-based materials. The analysis identifies activation overpotential as the dominant system bottleneck and demonstrates that realistic improvements in Tafel slope and exchange current density are sufficient to achieve automotive-scale hydrogen production at approximately 1.5–2 kW electrical input with reaction areas of 5–6 m². By connecting abstract design space, probabilistic robustness, and real catalyst systems, EROC v3 shifts the hydrogen vehicle discussion from theoretical feasibility to concrete, design-constrained optimization.