Effect of Operating Conditions on the Water Transport Phenomena at the Cathode of Polymer Electrolyte Membrane Fuel Cell

2009 ◽  
Author(s):  
Sang Hern Seo ◽  
Chang Sik Lee
Keyword(s):  
Fuel Cell ◽  
Polymer Electrolyte ◽  
Water Transport ◽  
Flow Rate ◽  
Water Droplet ◽  
Polymer Electrolyte Membrane ◽  
Transport Phenomena ◽  
Operating Conditions ◽  
Water Flooding ◽  
Electrolyte Membrane

Water management is very important for polymer electrolyte membrane fuel cell because the fuel cell performance is decreased by flooding phenomena generated by liquid water in the cathode channels. In addition, the proton conductivity and water transport of membrane could become different by hydration contents of membrane. This study is observed water transport phenomena of cathode channels with a polymer electrolyte membrane fuel cell according to various operating conditions. In order to obtain the water images, the transparent fuel cell consists of polycarbonate window of the cathode end plate and gold coated stainless steel as the flow field and current collector of the cathode. To investigate the effects of operating conditions on the water transport, experiments were conducted under various operating conditions such as cell temperature, cathode flow rate and cathode backpressure. As operating time elapsed, it is observed that the water droplet formation, growth, coalescence and removal occurred in the cathode channel. It can be known that the high cathode flow rate prevents water flooding by removal of water in the cathode flow channel. Also, the quantity of water droplet was increased by the high cathode backpressure.

Experimental Study of Effects of Operating Conditions on Water Transport Phenomena in the Cathode of Polymer Electrolyte Membrane Fuel Cell

2011 ◽  
Vol 8 (6) ◽  
Author(s):  
Sang Hern Seo ◽  
Chang Sik Lee
Keyword(s):  
Fuel Cell ◽  
Polymer Electrolyte ◽  
Water Transport ◽  
Flow Rate ◽  
Polymer Electrolyte Membrane ◽  
Operating Time ◽  
Current Collector ◽  
Operating Conditions ◽  
Fuel Cell Performance ◽  
Electrolyte Membrane

Water management in polymer electrolyte membrane fuel cells is important because fuel cell performance may be lower when flooding emerges. In addition, the proton conductivity and water transport coefficient in the membrane depend on the hydration of the membrane. In this study a water transport phenomenon in the cathode channels of a polymer electrolyte membrane fuel cell was investigated under various operating conditions. To obtain images of the water the transparent fuel cell had a polycarbonate window installed at the cathode end plate, and gold-coated stainless steel was used for the flow field and current collector of the cathode. The effects of operating conditions on water transport manipulated operating parameters such as cell temperature, cathode flow rate, and cathode backpressure. As the operating time elapsed, it was observed that water droplet formation, growth, coalescence, and removal occurred in the cathode channel. It concluded that a high cathode flow rate prevented flooding by removing water from the cathode flow channel. Also, the quantity of water droplets increased with a high cathode backpressure.

scholarly journals Analyzing and Modeling of Water Transport Phenomena in Open-Cathode Polymer Electrolyte Membrane Fuel Cell

2021 ◽  
Vol 11 (13) ◽  
pp. 5964
Author(s):  
Wei-Wei Yuan ◽  
Kai Ou ◽  
Seunghun Jung ◽  
Young-Bae Kim
Keyword(s):  
Water Management ◽  
Fuel Cell ◽  
Polymer Electrolyte ◽  
Water Transport ◽  
Polymer Electrolyte Membrane ◽  
Transport Phenomena ◽  
Catalyst Layer ◽  
Pem Fuel Cell ◽  
Electrolyte Membrane ◽  
Gas Channel

Water management is one issue that must be surpassed to ensure high membrane proton conductivity and adequate reactant transport in the membrane-electrode assembly (MEA) simultaneously. A well-designed water management system is based on a comprehensive understanding of water transport in the inner part of the polymer electrolyte membrane (PEM) fuel cell. In this work, the water transport phenomena in the MEA PEM fuel cell are analyzed by using a mathematical model. The transport of diluted species interface is used to model the transport of water in the ionomer phase in the catalytic layer and the membrane domains. The molecular flux of water is defined using Nernst–Planck equations, including migration and Fickian diffusion using parameters obtained experimentally for diffusivity and mobility based on water drag for a fully humidified membrane. The proposed model 1D model includes anode gas channel, cathode gas channel, anode gas diffusion layer (GDL), cathode GDL, anode catalyst layer, cathode catalyst layer, and proton exchange membrane. Water activity, ionomer conductivity, and output voltage are predicted by changing the humidity on the anode side of the fuel cell.

Sensitivity of Thermal Transport and Phase-Change in Thin Porous Layers to the Distribution of the Solid Matrix

2013 ◽  
Author(s):  
Vinaykumar Konduru ◽  
Ezequiel Medici ◽  
Jeffrey S. Allen
Keyword(s):  
Fuel Cell ◽  
Mass Transport ◽  
Polymer Electrolyte ◽  
Solid Phase ◽  
Polymer Electrolyte Membrane ◽  
Operating Conditions ◽  
Transport Layer ◽  
Solid Matrix ◽  
High Water Content ◽  
Electrolyte Membrane

Understanding the water transport in the Porous Transport Layer (PTL) is important to improve the operational performance of polymer electrolyte membrane fuel cells (PEMFC). High water content in the PTL and flow channel decreases the transport of the gas reactants to the polymer electrolyte membrane. Dry operating conditions result in increased ohmic resistance of the polymer electrolyte membrane. Both cases result in decreased fuel cell performance. Multi-phase flow in the PTL of the fuel cell is simulated as a network of pores surrounded by the solid material. The pore-phase and the solid-phase of the PTL are generated by varying the parameters of the Weibull distribution function. In the network model, the mass transfer takes place in the pore-phase and the bulk heat transfer takes place in the both the solid-phase and liquid phase of the PTL. Previous studies have looked at the thermal and mass transport in the porous media considering the pore size distribution. In the present study, the sensitivity of the thermal and mass transport to the different arrangements of the solid-phase is carried out and the effect of different solid-phase distributions on the thermal and liquid transport in PTL of PEM fuel cell are discussed.

Current Distribution in a Polymer Electrolyte Membrane Fuel Cell Under Flooding Conditions

2009 ◽  
Author(s):  
A. Jamekhorshid ◽  
G. Karimi ◽  
X. Li
Keyword(s):  
Fuel Cell ◽  
Polymer Electrolyte ◽  
Current Distribution ◽  
Current Density ◽  
Polymer Electrolyte Membrane ◽  
Operating Conditions ◽  
Average Current Density ◽  
Electrolyte Membrane ◽  
Wide Range ◽  
Average Current

Non-uniform current distribution in polymer electrolyte membrane fuel cells results in local over-heating, accelerated ageing, and lower power output than expected. This issue is very critical when fuel cell experiences water flooding. In this work, the performance of a PEM fuel cell is investigated under cathode flooding conditions. A partially flooded GDL model is proposed to study local current density distributions along flow fields over a wide range of cell operating conditions. The model results show as cathode inlet humidity and/or cell pressure increase the average current density for the unflooded portions of the cell increases but the system becomes more sensitive to flooding. Operating the cell at higher temperatures would lead to higher average current densities and the chance of system being flooded is reduced. In addition, higher cathode stoichiometries prevent system flooding but the average current density remains almost constant.

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