Redesigning protonic ceramic electrochemical cells to lower the operating temperature.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Protonic ceramic electrochemical cells (PCECs) offer potential for power generation and hydrogen production.
• Current PCEC technology operates at high temperatures (450–600°C), limiting material choices and increasing costs.
• Lowering operating temperatures to below 450°C is crucial for broader adoption and cost reduction.

Purpose of the Study:

• To redesign PCECs for efficient operation at lower temperatures (<450°C).
• To enhance electrolyte and electrode performance for improved energy conversion.
• To demonstrate the feasibility of low-temperature PCECs for fuel cell and electrolysis applications.

Main Methods:

• Fabrication of single-grain-thick, chemically homogeneous, and robust electrolytes.
• Development of nano-micro structured positive electrodes.
• Performance testing of PCECs in fuel cell mode (H2, NH3, CH4 fuels) and steam electrolysis mode.

Main Results:

• Achieved peak power densities of 1.6 W/cm² (H2), 0.5 W/cm² (NH3), and 0.3 W/cm² (CH4) at 450°C.
• Demonstrated high current density (>0.6 A/cm²) and Faradaic efficiency (>90%) in steam electrolysis at 400°C.
• Exhibited exceptional durability (>2000 hours) with minimal degradation (<0.01 mV/100h) at 400°C.

Conclusions:

• Redesigned PCECs enable efficient operation at lower temperatures (<450°C).
• The novel electrolyte and electrode designs contribute to high performance and durability.
• These advancements pave the way for cost-effective ceramic electrochemical cell technology.