Above and beyond the Lab ScaleCreating a kW-Sized AEM Electrolyzer Validated by In-Situ Distribution of Relaxation...

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Engineering

Background:

• Anion exchange membrane water electrolyzers (AEMWEs) are crucial for green hydrogen production.
• Current AEMWE technology is limited to small electrode sizes (1-10 cm²), hindering scalability.
• Scaling up AEMWEs is essential for advancing their technology readiness level.

Purpose of the Study:

• To design, characterize, and validate a large-scale, 1 kW anion exchange membrane water electrolyzer (AEMWE) stack.
• To demonstrate the scalability and efficacy of non-precious metal (non-PGM) electrodes in large-area AEMWEs.
• To assess the performance and uniformity of a 500 cm² AEMWE stack.

Main Methods:

• Designed and constructed a 1 kW, 500 cm² (5 × 100 cm²) non-PGM AEMWE stack with integrated corrosion protection, heating, and control systems.
• Validated stack performance at a current density of 1.0 A cm⁻².
• Conducted comprehensive statistical analysis and electrochemical impedance spectroscopy (EIS) with distribution of relaxation times (DRT) analysis.

Main Results:

• The 500 cm² AEMWE stack operated stably at 1.0 A cm⁻² with an energy efficiency of 53.2 kWh kg_H₂⁻¹.
• Statistical analysis confirmed uniform performance across five cells within the stack.
• DRT analysis provided kinetic insights comparable to lab-scale electrodes, validating non-PGM electrode scalability and efficacy.

Conclusions:

• The developed 1 kW, 500 cm² non-PGM AEMWE stack demonstrates successful scalability for efficient hydrogen production.
• The study confirms the viability of non-PGM catalysts and DRT analysis for large-scale AEMWE applications.
• This advancement is critical for accelerating the commercialization of AEMWE technology.