Articles techniques et présentations

Electrolytic hydrogen production stands as a beacon of promise within the realm of sustainable energy technologies, owing to its remarkable potential for yielding hydrogen with high energy efficiency and enabling long-term energy storage. Among the gamut of hydrogen production techniques, Alkaline Water Electrolysis (AWE) emerges as a beacon of promise, distinguished by its robustness, economic viability, and technological maturity. However, conventional Alkaline Water Electrolyzers (AWEs) grapple with intrinsic limitations stemming from elevated internal ohmic resistance, which necessitates their operation at conservative current densities. In a significant stride toward surmounting these limitations, the innovative Zero Gap configuration of Alkaline Water Electrolyzers (ZGAWE) emerges as a transformative concept. By substantially mitigating the ohmic overpotential drop, this avant-garde design paradigm transcends the constraints of conventional systems, enabling operation at elevated current densities and consequently bestowing heightened energy conversion efficiency. To engender a comprehensive exploration of the intricate dynamics governing the Zero Gap configuration AWE cell, a sophisticated and rigorous two-dimensional (2D) two-phase (2P) electrochemistry-transport coupled model was meticulously formulated using the industry-standard COMSOL Multiphysics software. This pioneering Multiphysics approach synergistically amalgamates the computational treatment of fluid dynamics transport equations with the intricate dance of electric charge and current conservation characterizing the electrochemical processes inherent to the ZGAWE cell. Leveraging the Euler-Euler approach, which adeptly captures the nuanced behavior of the two-phase bubbly flow, the model unravels the complex interplay of forces, currents, and potentials within the electrochemical system. In parallel, the model quantifies the electrical response through the intricate contours of the polarization curve during ZGAWE cell operation, enabling a nuanced understanding of performance under varying conditions. The model's efficacy and accuracy were rigorously gauged through a series of meticulous comparative analyses and rigorous empirical validation exercises, wherein it was benchmarked against the standard non-zero gap alkaline electrolyzer. This scrutiny spanned diverse operational parameters encompassing temperature gradients, electrolyte concentration gradients, electrode charge transfer coefficients, and separator porosity variations. Extending its horizons to industrial-scale parameters, the model was instrumental in elucidating the intricate ramifications of membrane leakage on ZGAWE cell performance, thus paving the way for insights that transcend the laboratory realm. In summation, this multidisciplinary endeavor propels the envelope of understanding surrounding the intricate interplay between electrochemical and transport phenomena within the ZGAWE cell. Beyond its academic significance, this endeavor holds pragmatic implications for harnessing hydrogen as a clean energy vector, underscoring the paramount importance of fine-tuning operational parameters for maximum efficiency and operational robustness.