Back to Search
Start Over
Differences in structure and property of carbon paper and carbon cloth diffusion media and their impact on proton exchange membrane fuel cell flow field design
- Source :
- Materials & Design. 32:861-868
- Publication Year :
- 2011
- Publisher :
- Elsevier BV, 2011.
-
Abstract
- Gas diffusion media (GDM) and flow fields perform the task of distributing the reactant gases uniformly over the active electrochemical area in proton exchange membrane (PEM) fuel cells. Carbon paper and carbon cloth are two commonly employed gas diffusion media in PEM fuel cells, and they differ widely in their structure and properties. Since the path of the reactant gases to the catalyst in the fuel cell electrodes involves passing through the flow fields as well as the GDM, a good design for a fuel cell requires an understanding of the interaction between these components. The focus of the present work is to study the impact of the difference in structure and properties of the diffusion media used, on the design of the PEM fuel cell flow field. Carbon paper and carbon cloth were characterized for the pressure drop they cause when used as GDMs, for channel intrusion, compressibility and electrical resistivity. Carbon cloth exhibits about 43-125% more intrusion into the channel in comparison with carbon paper for the conditions tested. This intrusion results in increased pressure drop in the flow channel especially at higher channel widths and at higher compression. Compression studies reveal that carbon cloth lacks compression rigidity and suffers considerable strain at lower stress values whereas carbon paper is relatively rigid in nature. The results indicate that the intrusion of carbon cloth into the channel, constraints the channel width in a flow field design if it were to be used with a carbon cloth GDM as opposed to a carbon paper GDM. Electrical resistivity measurements were carried out and a simple mathematical model has been developed for the potential drop in the GDM. The model indicates that even from the perspective of electrical properties, use of carbon cloth GDM constraints the channel width that is permissible in flow field design. � 2010 Elsevier Ltd.
- Subjects :
- Pressure drop
business.product_category
Materials science
business.industry
Electrical engineering
Proton exchange membrane fuel cell
A-carbon
B. Fabric
Carbon cloths
Carbon paper
Channel widths
E. Electrical
E. Mechanical
Electrical property
Electrical resistivity
Electrical resistivity measurements
Flow channels
Flow-field design
Fuel cell electrodes
Gas diffusion media
Lower stress
PEM fuel cell
Potential drop
Proton exchange membranes
Reactant gas
Structure and properties
Diffusion in gases
Electric conductivity
Flow fields
Mathematical models
Paper
Proton exchange membrane fuel cells (PEMFC)
Protons
Structural design
Carbon Papers
Diffusion
Fuel Cells
Mathematical Models
Pressure Gradient
Resistivity
Structural Design
Electrical resistivity and conductivity
Electrode
Compressibility
Gaseous diffusion
Composite material
business
Voltage drop
Subjects
Details
- ISSN :
- 02613069
- Volume :
- 32
- Database :
- OpenAIRE
- Journal :
- Materials & Design
- Accession number :
- edsair.doi.dedup.....8f8f1f07869a7218a8b69639a39f59cc