Premium
Mathematical modeling of solid oxide fuel cells at high fuel utilization based on diffusion equivalent circuit model
Author(s) -
Bao Cheng,
Shi Yixiang,
Li Chen,
Cai Ningsheng,
Su Qingquan
Publication year - 2010
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.12053
Subject(s) - overpotential , solid oxide fuel cell , thermodynamics , mass transfer , thermal diffusivity , tortuosity , oxide , diffusion , gaseous diffusion , chemistry , polarization (electrochemistry) , mechanics , electrochemistry , electrode , equivalent circuit , materials science , voltage , electrical engineering , engineering , physics , composite material , anode , organic chemistry , porosity
Mass transfer and electrochemical phenomena in the membrane electrode assembly (MEA) are the core components for modeling of solid‐oxide fuel cell (SOFC). The general MEA model is simply governed with the Stefan‐Maxwell equation for multicomponent gas diffusion, Ohm's law for the charge transfer and the current‐overpotential equation for the polarization calculation. However, it has obvious discrepancy at high‐fuel utilization or high‐current density. An advanced MEA model is introduced based on the diffusion equivalent circuit model. The main purpose is to correct the real‐gas concentrations at the triple‐phase boundary by assuming that the resistance of surface diffusion is in series with that of the gaseous bulk diffusion. Thus, it can obtain good prediction of cell performance in a wide range by avoiding the decrement of effective gas diffusivity via unreasonable increment of the electrode tortuosity in the general MEA model. The mathematical model has been validated in the cases of H 2 H 2 O, COCO 2 and H 2 CO fuel system. © 2009 American Institute of Chemical Engineers AIChE J, 2010