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Journal of Applied Electrochemistry

, Volume 14, Issue 2, pp 135–143 | Cite as

Model of the isotropic anode in the molten carbonate fuel cell

  • J. Jewulski
  • L. Suski
Papers

Abstract

An Isotropic one-dimensional model is proposed for the porous anode of a molten carbonate fuel cell, requiring the thickness of the electrolyte film in the pores as the only one adjustable parameter. The solution of the model equations is presented in a general form and calculations are made by approximation. The wetting of the whole electrode inner surface by the electrolyte is assumed. The model shows that, practically, the current is generated in a thin reaction zone in the electrode. The model may be fitted well to the experimental polarization curves [4], when 0.057 μm is the electrolyte film thickness.

Keywords

Physical Chemistry Film Thickness Fuel Cell Model Equation Polarization Curve 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Nomenclature

ai,bi,ci

electrode reaction orders

ck

molar concentration of thekth gas component at the electrode/electrolyte interface

ck

equilibrium molar concentration of thekth gas component

d

parameter in Equation 21

Dk

diffusion coefficient of thekth component

F

Faraday's constant

Hk

Henry's constant of thekth component

i

Faradaic current density

i0

exchange current density

iklim

limiting current density of thekth reagent

je,jm

ionic and electronic current density, respectively

jT

total anodic current density

k

rate constant in Equation 19

l

electrode thickness

pk

partial pressure of thekth component

PD

penetration depth

Q

parameter, defined by Equation 41

R

gas constant

S

specific internal surface of the electrode

T

temperature

VE

relative electrolyte volume in the electrode

x

dimensionless coordinate,x=z/l

ZF

η(i) function slope at zero current

Z

total electrode impedance per unit area of electrode

β

symmetry coefficient

δ

electrolyte film thickness

η

overpotential

η0,η1

overpotentials at the gas/electrode (x=0) and the electrode/electrolyte (x=1) interfaces, respectively

η′,η″

dummy variables of the integration

ηm

measured overpotential

kE,kM

specific electrolyte and electrode metal conductivity, respectively

keeff,kMeff

effective electrolyte and electrode metal conductivity, respectively

v

stoichiometric number

ξ

tortuosity factor

φE,φM

electrolyte and electrode metal potentials, respectively

Δφeq

equilibrium electrode metal-electrolyte potential difference

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References

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Copyright information

© Chapman and Hall Ltd. 1984

Authors and Affiliations

  • J. Jewulski
    • 1
  • L. Suski
    • 1
  1. 1.Institute of Physical Chemistry, Molten Salts LaboratoryPolish Academy of SciencesKrakówPoland

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