A high-performance capillary-fed electrolysis cell promises more cost-competitive renewable hydrogen

Area of Science:

• Green hydrogen production
• Electrochemical energy conversion
• Sustainable energy technologies

Background:

• Renewable hydrogen is crucial for decarbonizing challenging sectors and mitigating global warming.
• Current renewable hydrogen production faces cost barriers due to low energy efficiency and high capital expenses of traditional water electrolyzers.

Purpose of the Study:

• To introduce a novel water electrolysis concept for enhanced efficiency and cost-competitiveness.
• To demonstrate a functional alkaline capillary-fed electrolysis cell.

Main Methods:

• Development of a capillary-fed water electrolysis cell with a porous inter-electrode separator.
• Utilizing capillary-induced water transport for bubble-free electrode operation.
• Performance testing of the cell at 0.5 A/cm² and 85°C.

Main Results:

• The capillary-fed electrolysis cell achieved a cell voltage of 1.51 V at 0.5 A/cm² and 85°C.
• Demonstrated a high energy efficiency of 98%, with an energy consumption of 40.4 kWh/kg hydrogen.
• Performance exceeded that of commercial water electrolysis cells.

Conclusions:

• The novel capillary-fed electrolysis offers significantly higher energy efficiency compared to conventional methods.
• This technology promises simplified balance-of-plant, paving the way for cost-competitive renewable hydrogen.
• The findings contribute to accelerating the adoption of green hydrogen for global decarbonization goals.