Analysis of multiphase tranport phenomena in PEMFCs by incorporating microscopic model for catalyst layer structure
Author
Summary, in English
The catalyst layer (CL) in polymer electrolyte membrane
(PEM) fuel cells is one of the key components regulating the
overall performance of the cell. In PEM fuel cells, there are two
CLs having identical composition for hydrogen oxidation (HO)
and oxygen reduction (OR) reactions. There are four phases inside
the CL, namely: carbon, Pt particles, ionomer and voids.
In this work, a micro-model of the cathode CL has been developed
mathematically using finite volume (FV) technique to reconstruct
the local structure and further investigate the transport
phenomena of reactants and product species, ions and electrons
by incorporating the above stated phases at the cathode
side only, due to the fact that the OR reactions are the rate limiting
as compared to HO reaction. The 3D CL has been reconstructed
based on a regularly distributed sphere’s method with
dimensions 4:14:14:1 μm3. Platinum particles combined
with carbon spheres (C/Pt) are regularly placed in the domain,
an ionomer layer of a given thickness is extruded from the sphere
surfaces. The C/Pt, ionomer and void distribution, as well as
Address all correspondence to this author. (munir [dot] khan [at] energy [dot] lth [dot] se)
the triple phase boundary (TPB) are analysed and discussed. A
microscopic model has been developed for water generation and
species transport including Knudsen diffusion through the voids
and the proton transport in the ionomer has been included here
to aim for the rigorousness of the work. In addition, the electrochemical
reactions have been simulated on the surface of Pt particles
fulfilling the TBP conditions.
(PEM) fuel cells is one of the key components regulating the
overall performance of the cell. In PEM fuel cells, there are two
CLs having identical composition for hydrogen oxidation (HO)
and oxygen reduction (OR) reactions. There are four phases inside
the CL, namely: carbon, Pt particles, ionomer and voids.
In this work, a micro-model of the cathode CL has been developed
mathematically using finite volume (FV) technique to reconstruct
the local structure and further investigate the transport
phenomena of reactants and product species, ions and electrons
by incorporating the above stated phases at the cathode
side only, due to the fact that the OR reactions are the rate limiting
as compared to HO reaction. The 3D CL has been reconstructed
based on a regularly distributed sphere’s method with
dimensions 4:14:14:1 μm3. Platinum particles combined
with carbon spheres (C/Pt) are regularly placed in the domain,
an ionomer layer of a given thickness is extruded from the sphere
surfaces. The C/Pt, ionomer and void distribution, as well as
Address all correspondence to this author. (munir [dot] khan [at] energy [dot] lth [dot] se)
the triple phase boundary (TPB) are analysed and discussed. A
microscopic model has been developed for water generation and
species transport including Knudsen diffusion through the voids
and the proton transport in the ionomer has been included here
to aim for the rigorousness of the work. In addition, the electrochemical
reactions have been simulated on the surface of Pt particles
fulfilling the TBP conditions.
Department/s
Publishing year
2011
Language
English
Document type
Conference paper
Topic
- Energy Engineering
Conference name
ASME International Mechanical Engineering Congress and Exposition (IMECE), 2011
Conference date
2011-11-11 - 2011-11-17
Conference place
Denver, CO, United States
Status
Published