scholarly journals Experimental study of gas diffusion layers nonlinear orthotropic behavior

2022 ◽  
Vol 334 ◽  
pp. 04020
Author(s):  
Marwa Ouerghemmi ◽  
Christophe Carral ◽  
Patrice Mele
Keyword(s):  
Mechanical Response ◽  
Gas Diffusion ◽  
Mechanical Tests ◽  
Manufacturing Processes ◽  
Machine Direction ◽  
Gas Diffusion Layers ◽  
Diffusion Layers ◽  
Out Of Plane ◽  
Optimal Stiffness ◽  
Orthotropic Behavior

One of the most important components of PEMFC is the gas diffusion layer (GDL), owing to its key role in the reactant diffusion, water management, thermal and electron conductivity. Therefore, the GDL must have an optimal stiffness to ensure these transport functions during numerous hydrothermal cycles. The understanding of its behavior is still a remaining issue. Its orthotropic mechanical behavior requires a series of mechanical characterizations in the plane of the fibers and out of plane. In addition, there are different manufacturing processes for GDL in sheet or roll form to optimize its functional properties. A macro porous layer (MPL) or different PTFE contents might be added by different manufacturers to optimize its performance. In this study, we have performed several mechanical tests differentiating between in plane and out of plane properties in order to characterize different GDLs available on the market. All of the experimental work has been done in the machine (MD) and cross machine direction (CD) according to the fiber orientation. The different GDL types were then classified into categories presenting similar mechanical response.

scholarly journals Numerical simulation of Effect of Contact Pressure on Gas Diffusion Layers deformation of a PEM Fuel Cell

2019 ◽  
Vol 286 ◽  
pp. 09006
Author(s):  
A. Atifi ◽  
K. El Bikri ◽  
M. Ettouhami
Keyword(s):  
Fuel Cell ◽  
Contact Pressure ◽  
Element Model ◽  
Bipolar Plate ◽  
Gas Diffusion ◽  
Gas Diffusion Layers ◽  
Fuel Cell Stack ◽  
Diffusion Layers ◽  
Dimensional Finite Element ◽  
Orthotropic Behavior

In this study, a two-dimensional, Finite Element model has been implemented based numerical modeling simulations to predict mechanical behavior of a representative unit of fuel cell stack deformation under three levels of contact pressure between GDL and bipolar plate assuming that the GDL deformation as a combination of elastic deformation and fibers slippage. The intrusion of the GDL into the channel was estimated. Indeed, with orthotropic behavior of the GDL, the proposed nonlinear orthotropic model converges towards the models of the literature as a function of the contact pressure level between the bipolar plate and the GDL (Gas Diffusion Layers).

Imaging of desaturation of the frozen gas diffusion layers by synchrotron X-ray radiography

2021 ◽  
Author(s):  
Yuzhou Zhang ◽  
Viral Hirpara ◽  
Virat Patel ◽  
Chen Li ◽  
Ryan Anderson ◽  
...  
Keyword(s):  
Gas Diffusion ◽  
Gas Diffusion Layers ◽  
X Ray ◽  
Diffusion Layers

scholarly journals Mass Transport Limitations of Water Evaporation in Polymer Electrolyte Fuel Cell Gas Diffusion Layers

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2967
Author(s):  
Adrian Mularczyk ◽  
Andreas Michalski ◽  
Michael Striednig ◽  
Robert Herrendörfer ◽  
Thomas J. Schmidt ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Liquid Water ◽  
Evaporative Cooling ◽  
Gas Diffusion ◽  
Polymer Electrolyte Fuel Cell ◽  
Ex Situ ◽  
Water Evaporation ◽  
Evaporative Water ◽  
Gas Diffusion Layers ◽  
Diffusion Layers

Facilitating the proper handling of water is one of the main challenges to overcome when trying to improve fuel cell performance. Specifically, enhanced removal of liquid water from the porous gas diffusion layers (GDLs) holds a lot of potential, but has proven to be non-trivial. A main contributor to this removal process is the gaseous transport of water following evaporation inside the GDL or catalyst layer domain. Vapor transport is desired over liquid removal, as the liquid water takes up pore space otherwise available for reactant gas supply to the catalytically active sites and opens up the possibility to remove the waste heat of the cell by evaporative cooling concepts. To better understand evaporative water removal from fuel cells and facilitate the evaporative cooling concept developed at the Paul Scherrer Institute, the effect of gas speed (0.5–10 m/s), temperature (30–60 °C), and evaporation domain (0.8–10 mm) on the evaporation rate of water from a GDL (TGP-H-120, 10 wt% PTFE) has been investigated using an ex situ approach, combined with X-ray tomographic microscopy. An along-the-channel model showed good agreement with the measured values and was used to extrapolate the differential approach to larger domains and to investigate parameter variations that were not covered experimentally.

Sign in / Sign up

Export Citation Format

Share Document