Abstract
This paper is devoted to the modeling and numerical optimization of proton-exchange membrane (PEM) water electrolysers for operation at elevated pressures (up to 130 bars). The model takes into account different geometrical parameters of the PEM cell, the kinetics of the hydrogen and oxygen evolution reactions, the electro-osmotic drag of water molecules, the permselectivity of the solid polymer electrolyte and associated gas cross-over phenomena. The role of various operating parameters (such as pressure, temperature, current density, flow rate of water) on cell efficiency, faradaic yield and heat produced during water electrolysis is evaluated and discussed. The model is also used for the purpose of optimizing the performances of PEM cells. In particular, optimal values of some critical operating parameters (current density, rate of water supplied to the anodes) are recommended.
Similar content being viewed by others
Abbreviations
- Cg, Cl, CH, CO (mol m−3):
-
Molar density of gas, liquid, hydrogen, oxygen.
- υg, υl (m s−1):
-
Velocity of gas and liquid.
- υ0 (m s−1):
-
Velocity of cooling water
- Pg, Pl, Pc (Pa):
-
Pressure of gas, liquid and capillary pressure
- Kp (m2):
-
Permeability of porous current collector
- Rp (m):
-
Average pore radius of porous current collector
- krl, krg:
-
Relative permeabilities of liquid and water
- s (adim.):
-
Saturation of porous current collector
- sfc (adim.):
-
Saturation at the current collector–flow channel interface
- scl (adim.):
-
Saturation at the current collector–catalytic layer interface
- θc (deg.):
-
Wetting angle of porous current collector
- ε (adim.):
-
Porosity of gas diffusion layer
- Rbc (m):
-
Critical bubble radius
- Ng, Nl, N (mol m−2 s−1):
-
Flux of gas, liquid, total flux
- Nga, Nla (mol m−2 s−1):
-
Gas and liquid fluxes at current collector–anodic layer interface
- Ngc, Nlc (mol m−2 s−1):
-
Gas and liquid fluxes at current collector–cathodic layer interface
- CH (mol m−3):
-
Hydrogen concentration in the gas phase
- Rp (m):
-
Effective pore radius
- iΣ, i0, ip (A m−2):
-
Total, useful, and parasitic current densities
- np (adim.):
-
Electro-osmotic drag coefficient
- Ps (Pa):
-
Pressure of saturated water vapor
- hm (m):
-
Membrane thickness
- h (m):
-
Gas diffusion layer thickness
- hfc (m):
-
Flow channel thickness
- ΔT (°C):
-
Temperature difference along the membrane-electrode assembly (MEA)
- SMEA (m2):
-
Active area of MEA
- iex (A m−2):
-
Exchange current density
- ρ m (Ohm−1 m−1):
-
Specific ionic conductivity of solid polymer electrolyte
- Cpw = 4,217 (J kg−1 K−1):
-
Specific heat of liquid water at T = 100 °C
- μl = 2.822 × 10−2 (Pa s):
-
Dynamic viscosity of liquid water at T = 100 °C and P = 13 MPa
- μH = 1.09 × 10−5 (Pa s):
-
Dynamic viscosity of hydrogen at T = 100 °C and P = 13 MPa
- μO = 2.47 × 10−5 (Pa s):
-
Dynamic viscosity of oxygen at T = 100 °C and P = 13 MPa
- σ = 0.05884 (Pa m):
-
Surface tension of water at T = 100 °C and P = 13 MPa
- ГH = 1.67 × 10−3 (mol mol−1):
-
Water solubility of hydrogen at T = 100 °C and P = 13 MPa
- ГO = 1.85 × 10−3 (mol/mol):
-
Water solubility of oxygen at T = 100 °C and P = 13 MPa
- Eeq = 1.29 (V):
-
Equilibrium cell voltage at T = 100 °C and P = 13.0 MPa
- ΔH° = −285.0 (kJ/mol):
-
Enthalpy change for reaction \( {\text{H}}_{2} + {\frac{1}{2}}{\text{O}}_{2} \to {\text{H}}_{2} {\text{O}}\left( l \right) \) at T = 100 °C
- np = 2.3 + 0.0212 · (T − 80):
-
Number of solvated water molecules associated with each proton (drag factor) in solid polymer electrolyte at full humidification versus temperature T in °C (approximated from data in [1]).
- \( D_{\text{OM}} = 2.44\, \times \,10^{ - 8} \exp \left( { - {\frac{2,100}{T}}} \right)\, \)(m2 s−1):
-
Diffusion coefficient of oxygen in solid polymer electrolyte at full humidification (approximated from data in [2]).
- \( D_{\text{HM}} = 5.65\, \times \,10^{ - 8} \exp \left( { - {\frac{2,100}{T}}} \right)\,\, \)(m2 s−1):
-
Diffusion coefficient of hydrogen in solid polymer electrolyte at full humidification (approximated from data in [2]).
- \( F_{\text{c}} (s) = \left( {\begin{array}{*{20}c} {1.417(1 - s) - 2.12(1 - s)^{2} + 1.263(1 - s)^{3} \quad } & {{\text{if}}\,\theta_{\text{c}} < 90^{^\circ } } \\ {1.417s - 2.12s^{2} + 1.263s^{3} } & {{\text{if}}\,\theta_{\text{c}} > 90^{^\circ } } \\ \end{array} } \right. \) :
-
Leverett function which is used to determine capillary pressure in porous media as a function of the wetting angle θ c (taken from [3]).
- \( E_{\text{r}} = E^{(0)} - 8.5\, \times \,10^{ - 4} \left( {T - 298.15} \right) + 4.308\, \times \,10^{ - 5} T\ln \left( {P_{\text{H}} P_{\text{O}}^{0.5} } \right) \) (V):
-
Reversible voltage of electrolysis cell as a function of temperature T and gas pressures.
- \( E_{\text{tn}} = - {\frac{{\Updelta H^{(0)} }}{2F}} - 8.5\, \times \,10^{ - 4} \left( {T - 298.15} \right) + 4.308\, \times \,10^{ - 5} T\ln \left( {P_{\text{H}} P_{\text{O}}^{0.5} } \right) \) (V):
-
Thermoneutral voltage of electrolysis cell as a function of temperature T and gas pressures.
References
Ren X, Gottesfeld S (2001) J Electrochem Soc 148(1):A87
Broka K, Ekdunge P (1997) J Appl Electrochem 27:117
Pasaogullari U, Wang CY (2004) J Electrochem Soc 151:A399
Millet P, Andolfatto F, Durand R (1996) Int J Hydrogen Energy 21:87
Grigoriev SA, Porembsky VI, Fateev VN (2006) Int J Hydrogen Energy 31:171
Ni M, Leung MKH, Leung DYC (2008) Energy Convers Manag 49:2748
Onda K, Murakami T, Hikosaka T, Kobayashi M, Notu R, Ito K (2002) J Electrochem Soc 149:A1069
Choi P, Bessarabov DG, Dattaa R (2004) Solid State Ion 175:535
Springer TE, Zawodzinski TA, Gottesfeld S (1991) J Electrochem Soc 138:2334
Springer TE, Wilson MS, Gottesfeld S (1993) J Electrochem Soc 140:3513
Nguyen T, White RE (1993) J Electrochem Soc 140:2178
He W, Yi JS, Nguyen TV (2000) AIChE J 46:2053
Wang ZH, Wang CY, Chen KS (2001) J Power Sources 94:40
You L, Liu H (2002) Int J Heat Mass Transfer 45:2277
Natarajan D, Nguyen TV (2001) J Electrochem Soc 148:A1324
Kaviany M (1999) Principles of heat transfer in porous media. Springer, New York
Wang CY, Cheng P (1997) Adv Heat Transfer 30:93
Grigoriev SA, Millet P, Korobtsev SV, Porembskiy VI, Pepic M, Etievant C, Puyenchet C, Fateev VN (2009) Int J Hydrogen Energy 34:5986
Tsyganov IA, Pozdnyakov AI, Richter E, Majtts MF (2007) Solid State Phys. Bull Nizhniy Novgorod Univ N.I. Lobachevsky 1:52 (in Russian)
Vasilev VV, Luchaninov AA, Strelnitsky VE, Tolstolutskaja GD, Kopanets IE, Sevidova EK, Kononenko VI (2005) Quest Nucl Sci Tech 3(86):167 (in Russian)
Acknowledgments
This work has been supported by the Federal Agency for Science and Innovations of the Russian Federation within the framework of the Federal Principal Scientific-Technical Programme “Researches and development on priority directions in development of scientific technological complex of Russia for 2007–2012” and by the Commission of the European Communities (6th Framework Programme, STREP project GenHyPEM no 019802). Financial support from the Global Energy International Prize Non-Profit Foundation (Grant no MG-2008/04/3) is also gratefully acknowledged.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Grigoriev, S.A., Kalinnikov, A.A., Millet, P. et al. Mathematical modeling of high-pressure PEM water electrolysis. J Appl Electrochem 40, 921–932 (2010). https://doi.org/10.1007/s10800-009-0031-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10800-009-0031-z