PEM Elektrolizörlerde Nem Yönetimi: Gaz Difüzyon Katmanı Tasarım Optimizasyonlarının Flooding Üzerindeki Etkileri

Öz

Proton Değişim Membranlı (PEM) elektrolizörlerde, suyun hidrojen ve oksijene ayrışması, uygulanan Doğru Akım (DA) kadar sistemin nem yönetimine de bağlıdır. Nem, proton iletkenliğini artırarak elektrokimyasal süreci desteklerken, aşırı birikimi (flooding) gaz difüzyonunu engelleyerek sistem performansını ciddi şekilde düşürmektedir. Bu çalışmada, nemin PEM elektrolizörlerdeki etkileri detaylı şekilde analiz edilmiş, flooding mekanizmaları incelenmiş ve Gaz Difüzyon Katmanı (GDL) tasarımının bu sorunun hafifletilmesine yönelik katkıları değerlendirilmiştir. Optimum nem seviyelerinde maksimum elektrolitik verim elde edilirken, yetersiz nem koşulları proton iletkenliğini sınırlandırmakta, aşırı su birikimi ise elektrot yüzeylerini tıkayarak gaz çıkışını engellemektedir. Bu bağlamda, GDL'nin hidrofobik kaplamalar, gradyan gözenek yapıları, mikrokanallar ve hibrit malzeme kombinasyonları ile optimize edilmesi, etkin su yönetimi sağlayarak flooding riskini minimize etmektedir.

Anahtar Kelimeler

• PEM Elektroliz
• Gaz Difüzyon Katmanı
• Flooding
• Nem

Moisture Management in PEM Electrolyzers: Effects of Gas Diffusion Layer Design Optimizations on Flooding

Öz

In Proton Exchange Membrane (PEM) electrolyzes, the decomposition of water into hydrogen and oxygen depends not only on the applied Direct Current (DC) but also on effective moisture management within the system. While humidity enhances proton conductivity and supports the electrochemical process, excessive accumulation (flooding) hinders gas diffusion and significantly degrades system performance. This study presents a detailed analysis of the effects of humidity in PEM electrolyzes, investigates flooding mechanisms, and evaluates the role of Gas Diffusion Layer (GDL) design in mitigating these challenges. While optimal humidity levels enable maximum electrolytic efficiency, insufficient moisture limits proton conductivity, and excessive water accumulation clogs electrode surfaces, obstructing gas release. In this context, optimizing the GDL through hydrophobic coatings, gradient pore structures, microchannel, and hybrid material combinations ensures effective water management and minimizes the risk of flooding.

Anahtar Kelimeler

• PEM Electrolyze
• Gas Diffusion Layer
• Flooding
• Humidity

Kaynakça

1. Agmon N. The grotthuss mechanism. Chemical Physics Letters 1995; 244(5-6): 456–462.
2. Alkhaldi S., Aziz M., Amrite A., Prasad AK. Parametric study of PEM water electrolyzer performance. Journal of Applied Electrochemistry 2025; 55(2): 327-343.
3. Anderson R., Zhang L., Ding Y., Blanco M., Bi X., Wilkinson DP. A critical review of two-phase flow in gas flow channels of proton exchange membrane fuel cells. Journal of Power Sources 2010; 195(15): 4531-4553.
4. Bakangura E., Wu L., Ge L., Yang Z., Xu T. Mixed matrix proton exchange membranes for fuel cells: State of the Art and Perspectives. Progress in Polymer Science, 2016; 57: 103–152.
5. Barbir F. PEM Fuel cells: Theory and Practice. Elsevier Academic Press; 2005.
6. Carmo M., Fritz DL., Mergel J., Stolten D. A comprehensive review on PEM water electrolysis. International Journal of Hydrogen Energy 2013; 38(12): 4901-4934.
7. Dalgıç BF. PEM yakıt hücresinde hidrojen gazındaki nem oranına bağlı olarak elektrik üretimindeki değişimin incelenmesi. Batman Üniversitesi Fen Bilimleri Enstitüsü Yüksek Lisans Tezi, sayfa no:27, Batman, Türkiye, 2019.
8. Genç Ö., Kallioğlu MA. Proton elektrolit membranlı (PEM) elektrolizörün sayısal incelenmesi ve deneysel doğrulanması. Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi 2018; 7(1): 370-380.

9. Grigoriev SA., Porembsky VI., Fateev VN. Pure hydrogen production by PEM electrolysis for hydrogen energy. International Journal of Hydrogen Energy 2006; 31(2): 171-175.
10. Hassan Q., Algburi S., Sameen AZ., Salman HM., Jaszczur M. Green hydrogen: A pathway to a sustainable energy future. International Journal of Hydrogen Energy 2024; 50: 310-333.
11. Ito H., Maeda T., Nakano A., Takenaka H. Properties of Nafion membranes under PEM water electrolysis conditions. International Journal of Hydrogen Energy 2011; 36(17): 10527-10540.
12. Karanfil G. Proton exchange membrane fuel cells: Thermodynamics, components and applications. Engineer and Machinery 2020; 61(698): 57–76.
13. Kreuer KD. Proton conductivity: Materials and mechanisms. Solid State Ionics 1996; 97(1-4): 1–15.
14. Kuhnert E., Mayer K., Heidinger M., Rienessel C., Hacker V., Bodner M. Impact of intermittent operation on photovoltaic-PEM electrolyzer systems: a degradation study based on accelerated stress testing. International Journal of Hydrogen Energy 2024; 55: 683-695.
15. Li H., Tang Y., Wang Z., Shi Z., Wu S., Song, D., Zhang J., Fatih K., Zhang J., Wang H., Liu Z., Rami A., Mazza A. A review of water flooding issues in the proton exchange membrane fuel cell. Journal of Power Sources 2008; 178(1): 103-117.
16. Marx D., Tuckerman ME., Hutter J., Parrinello M. The nature of the hydrated excess proton in water. Nature 1999; 397(6719): 601–604.
17. Meyer Q., Yang C., Cheng Y., Zhao C. Overcoming the electrode challenges of high-temperature proton exchange membrane fuel cells. Electrochemical Energy Reviews 2023; 6: 16. https://doi.org/10.1007/s41918-023-00180-y
18. Nam JH., Kaviany M. Effective diffusivity and water-saturation distribution in single- and two-layer PEMFC diffusion medium. International Journal of Heat and Mass Transfer 2003; 46(24): 4595-4611.
19. Özdemir SN., Taymaz I., San FGB., Okumuş E. Performance assessment and optimization of the PEM water electrolyzer by coupled response surface methodology and finite element modeling. Fuel 2024; 365: 131138.
20. Park J., Li X., Tran D. Effects of flooding and hydrophobic polymer treatment on the performance of PEM fuel cells. Journal of Power Sources 2007; 172(2): 660-669.
21. Prakash M., Maiyelvaganan KR., Giri Lakshman N., Al-Mogren M., Hochlaf M. Formation of eigen or zundel features at protonated water cluster–aromatic ınterfaces. ChemPhysChem 2023; 24(16): e202300267.
22. Vlachaki E., Lekatsas K., Berning T. A thermodynamic analysis of a proton exchange membrane electrolyzer. ECS Transactions 2024; 114(5): 581.
23. Wallnöfer-Ogris E., Grimmer I., Ranz M., Höglinger M., Kartusch S., Rauh J., Macherhammer MG., Grabner B., Trattner A. A review on understanding and identifying degradation mechanisms in PEM water electrolysis cells: Insights for stack application, development, and research. International Journal of Hydrogen Energy 2024; 65: 381-397.
24. Wang CR., Stansberry JM., Mukundan R., Chang HMJ., Kulkarni D., Park AM., Plymil AB., Firas NM., Liu CP., Lang JT., Lee JK., Tolouei NE., Yu M., Wang CH., Zhu G., Brouwer J., Atanassov P., Capuano CB., Mittelsteadt., Peng X., Zenyuk IV. Proton exchange membrane (PEM) water electrolysis: cell-level considerations for gigawatt-scale deployment. Chemical Reviews 2025; 125(3): 1257–1302.
25. Wang Y., Chen KS., Mishler J., Cho SC., Adroher XC. A review of polymer electrolyte membrane fuel cells: Technology, applications, and needs on fundamental research. Applied Energy 2011; 88(4): 981-1007.
26. Weber AZ., Newman J. Modeling transport in polymer-electrolyte fuel cells. Chemical Reviews 2004; 104(10): 4679-4726.
27. Web1: https://www.fuelcellstore.com/gas-diffusion-layer-characteristics-and-modeling. Erişim tarihi: 11.01.2025.
28. Zenyuk IV., Parkinson DY., Hwang G., Weber AZ. Probing water distribution in compressed fuel-cell gas-diffusion layers using X-ray computed tomography. Electrochemistry Communications 2015; 53: 24-28.