Improving tubular protonic ceramic fuel cell performance by compensating Ba evaporation via a Ba-excess optimized proton conducting electrolyte synthesis strategy

• Published in: JPhys Energy 2024-07, Vol.6 (3), p.35004
• Main Authors: Kim, You-Dong, Kim, In-Ho, Meisel, Charlie, Herradón, Carolina, Rand, Peter W, Yang, Jayoon, Kim, Hyun Sik, Sullivan, Neal P, O’Hayre, Ryan
• Format: Article
• Language: English
• Subjects: Barium; barium evaporation; Ceramics; Chemical properties; Electrochemical analysis; Electrolytic cells; Energy conversion; Evaporation; Fuel cells; High temperature; protonic ceramic electrolyte; protonic ceramic fuel cells; Protons; reducing sintering temperature; tubular protonic ceramic fuel cells
• ISSN: 2515-7655; 2515-7655
• DOI: 10.1088/2515-7655/ad5760

Protonic ceramic fuel cells (PCFCs) are emerging as a promising technology for reduced temperature ceramic energy conversion devices. The BaCe 0.4 Zr 0.4 Y 0.1 Yb 0.1 O 3− δ (BCZYYb4411) electrolyte is notable for its high proton conductivity. However, the tendency of barium to volatilize in BCZYYb4411 during high-temperature sintering compromises its chemical stability and performance. This study investigates the effects of intentionally incorporating excess barium into BCZYYb4411, formulated as Ba 1+ x Ce 0.4 Zr 0.4 Y 0.1 Yb 0.1 O 3− δ (where x = 0, 0.1, 0.2, and 0.3), with the aim of compensating barium evaporation and enhancing the physical and chemical properties. We find that excess barium results in a greater shrinkage rate, facilitating a denser electrolyte structure. This barium-enriched electrolyte demonstrates improved electrochemical performance by effectively counteracting the deleterious effects of barium evaporation. Applying this strategy to tubular PCFCs, we achieved a peak power density of 480 mW∙cm −2 at 600 °C. This unique approach provides a simple, tunable, and easy-to-implement processing modification to achieve high-performance tubular PCFC.