Effects of Operating Parameters on the Current Density Distribution in Proton Exchange Membrane Fuel Cells

2006 ◽  
Vol 3 (4) ◽  
pp. 464-476 ◽  
Author(s):  
Y. Zhang ◽  
A. Mawardi ◽  
R. Pitchumani
Keyword(s):  
Fuel Cell ◽  
Density Distribution ◽  
Current Density ◽  
Proton Exchange Membrane ◽  
Current Density Distribution ◽  
Pem Fuel Cell ◽  
Proton Exchange ◽  
Operating Conditions ◽  
Local Current Density ◽  
Local Current

During the operation of a proton exchange membrane (PEM) fuel cell, significant variation of the local current density could exist across the cell causing sharp temperature and stress gradients in certain points, and affecting the water management, all of which severely impact the cell performance and reliability. The variation of local current density is a critical issue in the performance of PEM fuel cell, and is influenced by the operating conditions. This article presents a model-assisted parametric design with the objective of determining the operating conditions which maximize the fuel cell performance while maintaining a level of uniformity in the current density distribution. A comprehensive two-dimensional model is adopted to simulate the species transport and electrochemical phenomena in a PEM fuel cell. Numerical simulations are performed for over a wide range of operating conditions to analyze the effects of various operating parameters on the variation of local current density of the fuel cell, and to develop design windows which serve as guideline in the design for maximum power density, minimum reactant stoichiometry, and uniform current density distribution.

Effect of operating conditions on current density distribution and high frequency resistance in a segmented PEM fuel cell

2012 ◽  
Vol 37 (9) ◽  
pp. 7736-7744 ◽  
Author(s):  
Dietmar Gerteisen ◽  
Nada Zamel ◽  
Christian Sadeler ◽  
Florian Geiger ◽  
Victor Ludwig ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Density Distribution ◽  
Current Density ◽  
High Frequency ◽  
Current Density Distribution ◽  
Pem Fuel Cell ◽  
Operating Conditions

Experiment Study on the Current Density Distribution of PEMFC by Segmented Cell Technology

2020 ◽  
Author(s):  
Tianwei Miao ◽  
Xu Xie ◽  
Chasen Tongsh ◽  
Jinqiao Liang ◽  
Yiqi Liang ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Density Distribution ◽  
Current Distribution ◽  
Current Density ◽  
Proton Exchange Membrane ◽  
Current Density Distribution ◽  
Cold Start ◽  
Proton Exchange ◽  
Cell Technology ◽  
Segmented Cell

Abstract The homogeneous of current density distribution is very important for performance and lifetime of proton exchange membrane fuel cell. In this study the current density distribution of a fuel cell with an active area of 108 cm2 has been investigated by using segmented cell technology. The σc is introduced to evaluate the homogeneity of current density and the smaller value of σc represents better homogeneity of current distribution. Under normal conditions, the experimental results show that the current density decreases progressively along the flow field at low cathode stoichiometry. It is also found that the homogeneity of current distribution has a strong correlation with the membrane hydration condition and always performs best at cathode relative humidity of 80% when anode condition keeps constant. The value of σc can be significantly reduced when cathode stoichiometry increases from 1.5 to 2.5, but it changes little when cathode stoichiometry continues to increase. During the cold start process, the evolutions of current density distribution are consistent with the temperature mappings. The form of stabilized heat core in the middle regions and homogeneous current density distribution are necessary for successful cold start. The value of σc also can be used to evaluate that the cold start succeeds or not.

The Effect of Inlet Parameters on Fluid Flow and Cell Performance at Cathode of a Proton Exchange Membrane Fuel Cell

2010 ◽  
Vol 7 (4) ◽  
Author(s):  
Utku Gulan ◽  
Hasmet Turkoglu ◽  
Irfan Ar
Keyword(s):  
Reynolds Number ◽  
Fuel Cell ◽  
Power Density ◽  
Current Density ◽  
Proton Exchange Membrane ◽  
Catalyst Layer ◽  
Pem Fuel Cell ◽  
Proton Exchange ◽  
Exchange Membrane ◽  
Oxygen Mole Fraction

In this study, the fluid flow and cell performance in cathode side of a proton exchange membrane (PEM) fuel cell were numerically analyzed. The problem domain consists of cathode gas channel, cathode gas diffusion layer, and cathode catalyst layer. The equations governing the motion of air, concentration of oxygen, and electrochemical reactions were numerically solved. A computer program was developed based on control volume method and SIMPLE algorithm. The mathematical model and program developed were tested by comparing the results of numerical simulations with the results from literature. Simulations were performed for different values of inlet Reynolds number and inlet oxygen mole fraction at different operation temperatures. Using the results of these simulations, the effects of these parameters on the flow, oxygen concentration distribution, current density and power density were analyzed. The simulations showed that the oxygen concentration in the catalyst layer increases with increasing Reynolds number and hence the current density and power density of the PEM fuel cell also increases. Analysis of the data obtained from simulations also shows that current density and power density of the PEM fuel cell increases with increasing operation temperature. It is also observed that increasing the inlet oxygen mole fraction increases the current density and power density.

Theoretical Analysis on the Autothermal Reforming Process of Ethanol as Fuel for a Proton Exchange Membrane Fuel Cell System

2006 ◽  
Vol 4 (4) ◽  
pp. 468-473 ◽  
Author(s):  
Alessandra Perna
Keyword(s):  
Fuel Cell ◽  
Proton Exchange Membrane ◽  
Pem Fuel Cell ◽  
Cell System ◽  
Autothermal Reforming ◽  
Proton Exchange ◽  
Operating Conditions ◽  
Hydrogen Yield ◽  
Fuel Cell System ◽  
Exchange Membrane

The purpose of this work is to investigate, by a thermodynamic analysis, the effects of the process variables on the performance of an autothermal reforming (ATR)-based fuel processor, operating on ethanol as fuel, integrated into an overall proton exchange membrane (PEM) fuel cell system. This analysis has been carried out finding the better operating conditions to maximize hydrogen yield and to minimize CO carbon monoxide production. In order to evaluate the overall efficiency of the system, PEM fuel cell operations have been analyzed by an available parametric model.

Direct Measurement of the Local Current Density Under Land-Channel Areas With Partially-Catalyzed MEAs

2012 ◽  
Author(s):  
Shan Jia ◽  
Hongtan Liu
Keyword(s):  
Fuel Cell ◽  
Current Density ◽  
Cell Voltage ◽  
Current Density Distribution ◽  
Cathode Side ◽  
High Cell ◽  
Land Area ◽  
Local Current Density ◽  
Local Current ◽  
Voltage Region

In a PEM fuel cell, local current density can vary drastically under the land and channel areas. The non-uniform current density distribution not only affects the overall performance of the fuel cell, but also leads to the local temperature and concentration differentiation on the MEA, which can cause problems such as membrane dehydration and catalyst degradations at certain locations. In order to investigate the local current performance, the objective of this work is to directly measure the local current density variations across the land and channel at the cathode in a PEM fuel cell with partially-catalyzed MEAs. First, the cathode flow plate is specially designed with a single-serpentine channel structure, and the gas diffusion electrode at cathode side is cut to fit this flow field size (5.0cm×1.3cm). Then five different partially-catalyzed MEAs with 1mm width corresponding to different locations from the middle of the gas channel to the middle of the land area are made. Fuel cells with each of the partially-catalyzed MEAs have been tested and the results provide the lateral current density distribution across the channel and the land areas. In the high cell voltage region, local current density is highest under the center of the land area and decreases toward the center of the channel area; while in the low cell voltage region local current density is highest under the middle of the channel area and decrease toward the center of the land area. Different flow rates are tested at the cathode side of the cell to study their effects on the local current density performance along the land-channel direction. And the results show that the flow rate barely has the effect on the current at the high cell voltage region, while it plays a significant role at the low voltage region due to the mass transport effect.

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