modelV_cell1
Extends from TransiEnt.Producer.Gas.Electrolyzer.Base.Physics.Voltage.PartialV_cell (partial model for PEM electrolyzer voltage).
Information
1. Purpose of model
This is a model for electrolyzer dynamics with varying voltage dependent on pressure, current density, and temperature.
2. Level of detail, physical effects considered, and physical insight
Voltage is modeled according to Espinosa-López et al 2018 based on pressure, temperature, and current. Contains overvoltage components from Nernst potential, activation, and ohmic overpotentials.
3. Limits of validity
Original model developed and validated in the range of 20-60 °C with operating pressure of 15-35 bar.
4. Interfaces
(no remarks)
5. Nomenclature
(no elements)
6. Governing Equations
Consist of voltage equations from Espinosa-López et al 2018 by default. Can modify membrane conductivity, reverse voltage, concentration overvoltage, and thermoneutral expresssions if desired.
7. Remarks for Usage
(no remarks)
8. Validation
Results have been validated against Espinosa-López et al 2018 published figures.
9. References
Z. Abdin, E. MacA. Gray, and C.J. Webb. Modelling and simulation of a proton exchange membrane (PEM) electrolyzer cell. International Journal of Hydrogen Energy, 40(39):13243-13257, 2015. doi:10.1016/j.ijhydene.2015.07.129.
Manuel Espinosa-López, Philippe Baucour, Serge Besse, Christophe Darras, Raynal Glises, Philippe Poggi, André Rakotondrainibe, and Pierre Serre-Combe. Modelling and experimental validation of a 46 kW PEM high pressure water electrolyser. Renewable Energy, 119, pp. 160-173, 2018. doi: 10.1016/J.RENENE.2017.11.081.
R. García-Valverde, N. Espinosa, and A. Urbina. Simple PEM water electrolyzer model and experimental validation. International Journal of Hydrogen Energy, 37(2):1927-1938, 2012. doi:10.1016/j.ijhydene.2011.09.027.
10. Version History
Created by John Webster (jcwebste@edu.uwaterloo.ca) October 2018.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | whichInput | input selector | |
| SI.Voltage | V_std | 1.23 | std reverse voltage of electrolysis of water |
| SI.Temperature | T_std | STD temperature | |
| Real | humidity_const | 14 | constant humidity |
| SI.Energy | E_exc | Activation energy for anode reaction, Espinosa 2018 | |
| SI.ChemicalPotential | E_pro | Temperature independent parameter for activation energy in proton transport, Espinosa 2018 | |
| SI.CurrentDensity | i_dens_0_an_std | A/m2, Exchange current density at Pt electrodes at T_std, Espinosa 2018 | |
| SI.Thickness | t_mem | PE membrane thickness - ref. Nafion 117 | |
| SI.Conductivity | mem_conductivity_ref | S/m, Membrane conductivity reference value at T_std,Espinosa 2018; typically [0.058,0.096]S/cm, 283(Agbli 2011) | |
| Real | alpha_an | charge transfer coefficient for anode, as Espinosa 2018 uses | |
| Real | z | 2 | Stoichiometric coefficient for transferred electrons; = 2 for electrolysis |
| Real | PaToAtm | 1/101325 | conversion factor for partial pressures |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Voltage | V_el_stack (from PartialV_cell) | PEM stack voltage | |
| SI.Voltage | V_cell (from PartialV_cell) | PEM cell voltage considering all included physical phenomena | |
| SI.Voltage | V_tn (from PartialV_cell) | Thermoneutral voltage- operating voltage at which net heat is 0 | |
| MembraneResistance | R_mem | Resistance of PE membrane to ionic flow | |
| SI.Voltage | V_rev | Voltage from Gibb's free energy incl. pressure and temp | |
| SI.Voltage | V_nernst | Nernst potential of Water electrolysis | |
| SI.Voltage | V_activation | Electrode overpotential contribution | |
| SI.Voltage | V_act_an | anode overpotential contribution | |
| SI.Voltage | V_act_cat | cathode overpotential contribution | |
| SI.Voltage | V_ohmic | Ohmic overpotential contribution | |
| SI.Voltage | V_conc | Concentration/diffusion overpotential contribution | |
| SI.Temperature | T_op | Operating stack temperature | |
| SI.CurrentDensity | i_dens_0_an | exchange current density at anode (i_0c can be neglected, small) | |
| SI.CurrentDensity | i_dens_a | Operating current density at anode, may also be needed for cathode | |
| SI.Conductivity | mem_conductivity | Conductivity of the PE membrane | |
| SI.Pressure | pp_H2O | Pa, vapour pressure of water vapour | |
| SI.Pressure | pp_H2 | Pa, partial pressure of H2 | |
| SI.Pressure | pp_O2 | Pa, partial pressure of O2, | |
| SI.Pressure | p_cat | cathode pressure | |
| V_concentration | concVoltageModel | ||
| PEMconductivity | membraneModel | ||
| V_thermoneutral | thermoneutralVoltageModel | ||
| V_reversible | reverseVoltageModel |
Contents
| Name | Description |
|---|---|
 PEMconductivity | |
 V_thermoneutral | |
 V_reversible | |
 V_concentration |