Comprehensive modeling of solid oxide electrolyzer cells for H2O and CO2 co-electrolysis

Year 2024, Volume: 9 Issue: 3, 381 - 397, 18.09.2024

Berre Kümük

https://doi.org/10.58559/ijes.1531980

Abstract

In this study, a 2D model of Solid Oxide Electrolysis Cells (SOECs) was developed to evaluate their performance in CO2 and H2O co-electrolysis. The numerical results were rigorously validated against prior studies, demonstrating high consistency. The investigation focused on understanding the influence of various factors such as support type and operating temperature on SOEC performance.Analysis of polarization and performance curves revealed that anode-supported and cathode-supported SOECs exhibited similar characteristics, while electrolyte-supported SOECs displayed lower performance due to inadequate conductivity and increased electrolyte thickness. At 1.6 V, the average current density for cathode-supported SOEC was approximately 2.3679 A/cm², slightly lower than that of anode-supported SOEC, which was approximately 2.3879 A/cm². Moreover, at an average current density of around 5.30 A/cm², the cathode-supported SOEC yielded an average power density of 10 W/cm², while the anode-supported SOEC achieved 10.1 W/cm².Furthermore, increasing temperature was found to enhance SOEC performance by promoting more efficient chemical reactions, reducing resistance, and improving gas production rates during electrolysis of H2O and CO2. However, careful consideration of optimal operating temperatures is essential to ensure cell durability and material lifespan.Moreover, comparing co-flow and cross-flow configurations highlighted minor differences in performance, with co-flow demonstrating slightly lower average current density but comparable power density at 1.6 V. Co-flow configuration was favored for its homogeneous operation, facilitating efficient gas mixing and diffusion, while counter-flow configurations may introduce heterogeneity, potentially affecting overall performance.Overall, this study provides valuable insights into optimizing SOEC performance and efficiency, emphasizing the importance of support type, operating temperature, and flow configuration in achieving optimal performance for CO2 and H2O co-electrolysis applications.

Keywords

Solid oxide electrolyzer, CO2 co-electrolysis, H2O co-electrolysis, Numerical modeling

References

• [1] Gómez SY, Hotza D. Current developments in reversible solid oxide fuel cells. Renewable and Sustainable Energy Reviews 2016;61:155–174.
• [2] Li Z, Zhang H, Xu H, Xuan J. Advancing the multiscale understanding on solid oxide electrolysis cells via modelling approaches: A review. Renewable and Sustainable Energy Reviews 2021;141:110863.
• [3] Tucker MC. Progress in metal-supported solid oxide electrolysis cells: A review. International Journal of Hydrogen Energy 2020;45:24203–24218.
• [4] Laguna-Bercero MA. Recent advances in high temperature electrolysis using solid oxide fuel cells: A review. Journal of Power Sources 2012;203:4–16.
• [5] Ni M, Leung MKH, Leung DYC. Technological development of hydrogen production by solid oxide electrolyzer cell (SOEC). International Journal of Hydrogen Energy 2008;33:2337–2354.
• [6] Lahrichi A, El Issmaeli Y, Kalanur SS, Pollet BG. Advancements, strategies, and prospects of solid oxide electrolysis cells (SOECs): Towards enhanced performance and large-scale sustainable hydrogen production. Journal of Energy Chemistry 2024;94:688–715.
• [7] Kamkeng ADN, Wang M, Hu J, Du W, Qian F. Transformation technologies for CO2 utilisation: Current status, challenges and prospects. Chemical Engineering Journal 2021;409:128138.
• [8] Zheng Y, Chen Z, Zhang J. Solid Oxide Electrolysis of H2O and CO2 to Produce Hydrogen and Low-Carbon Fuels. Electrochemical Energy Reviews 2021;4:508–517.
• [9] Ramdin M, De Mot B, Morrison ART, Breugelmans T, Van Den Broeke LJP, Trusler JPM, et al. Electroreduction of CO2/CO to C2 Products: Process Modeling, Downstream Separation, System Integration, and Economic Analysis. Industrial and Engineering Chemistry Research 2021;60:17862–17880.
• [10] Song Y, Zhang X, Xie K, Wang G, Bao X. High-Temperature CO2 Electrolysis in Solid Oxide Electrolysis Cells: Developments, Challenges, and Prospects. Advanced Materials 2019;31:1–18.
• [11] Xu H, Chen B, Irvine J, Ni M. Modeling of CH4-assisted SOEC for H2O/CO2 co-electrolysis. International Journal of Hydrogen Energy 2016;41:21839–21849.
• [12] Song Y, Zhou Z, Zhang X, Zhou Y, Gong H, Lv H, Liu Q, Wang G, Bao X. Pure CO2 electrolysis over a Ni/YSZ cathode in a solid oxide electrolysis cell. Journal of Materials Chemistry A 2018;6:13661–13667.
• [13] Wang Y, Banerjee A, Deutschmann O. Dynamic behavior and control strategy study of CO2/H2O co-electrolysis in solid oxide electrolysis cells. Journal of Power Sources 2019;412:255–264.
• [14] Luo Y, Shi Y, Chen Y, Li W, Jiang L, Cai N. Pressurized tubular solid oxide H2O/CO2 electrolysis cell for direct power-to-methane. AIChE Journal 2020;66:1–14.
• [15] Mahmood A, Bano S, Yu JH, Lee KH. Performance evaluation of SOEC for CO2/H2O co-electrolysis: Considering the effect of cathode thickness. Journal of CO2 Utilization 2019;33:114–120.
• [16] Ni M. Computational fluid dynamics modeling of a solid oxide electrolyzer cell for hydrogen production. International Journal of Hydrogen Energy 2009;34:7795–7806.
• [17] Ni M. Modeling of SOFC running on partially pre-reformed gas mixture. International Journal of Hydrogen Energy 2012;37:1731–1745.
• [18] COMSOL Multiphysics. The COMSOL Multiphysics Reference Manual. Manual 2015:1–1336.
• [19] Ni M. 2D thermal modeling of a solid oxide electrolyzer cell (SOEC) for syngas production by H2O/CO2 co-electrolysis. International Journal of Hydrogen Energy 2012;37:6389–6399.