Distribution of current density across the active area at various stoichiometry ratios using the JRC ZERO∇CELL single cell PEM fuel cell testing hardware

The performance of the PEM fuel cell directly depends on the partial pressure of provided reactants, namely hydrogen and oxygen. Since reactants are consumed in the fuel cell reaction, partial pressure of reactants decreases in the direction of reactants flow. This well-known mechanism makes the performance of the fuel cell dependent on the stoichiometry ratios of input reactants. The JRC ZERO∇CELL, a single cell PEM fuel cell testing setup, is developed to provide as much as possible uniform operating conditions at the 10cm2 active area specimen, hence giving uniform current density across the active area of the cell. To investigate what is the real gradient of current density across the active area for the JRC ZERO∇CELL at various reactant stoichiometry ratios, segmented bi-polar plates and current collectors are developed. This study presents experimental investigation of the current density distribution across the active area of the JRC ZERO∇CELL setup at range of reactant stoichiometry ratios from λ = 2 up to λ = 15. Current density gradients are considered along the gas flow as well as in the transverse direction. The experimental results show that the current density gradient across the active area, although dependant on the reactants stoichiometry ratios, is relatively small as compared with a wide range of investigated stoichiometry ratios.

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

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2012.02.024 ◽

2012 ◽

Vol 37 (9) ◽

pp. 7736-7744 ◽

Cited By ~ 42

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

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Analysis of Water Morphology in the Active Area and Channel-to-Manifold Transitions of a PEM Fuel Cell

ASME 2014 12th International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2014-6565 ◽

2014 ◽

Author(s):

Daniel J. Fenton ◽

Jeffrey J. Gagliardo ◽

Thomas A. Trabold

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Flow Field ◽

Current Density ◽

Liquid Water ◽

Pem Fuel Cells ◽

Operating Conditions ◽

Active Area ◽

Water Volume ◽

Crossover Point

To achieve optimal performance of proton exchange membrane (PEM) fuel cells, effective water management is crucial. Cells need to be fabricated to operate over wide ranges of current density and cell temperature. To investigate these design and operational conditions, the present experiment utilized neutron radiography for measurement of in-situ water volumes of operating PEM fuel cells under varying operating conditions. Fuel cell performance was found to be generally inversely correlated to liquid water volume in the active area. High water concentrations restrict narrow flow field channels, limiting the reactant flow, and causing the development of performance-reducing liquid water blockages (slugs). The analysis was performed both quantitatively and qualitatively to compare the overall liquid water volume within the cell to the flow field geometry. The neutron image analysis results revealed interesting trends related to water volume as a function of time. At temperatures greater than 25°C, the total liquid water volume at start-up in the active area was the lowest at 1.5 A/cm2. At 25°C, 0.1 A/cm2 performed with the least amount of liquid water accumulation. However, as the reaction progressed at temperatures above 25°C, there was a crossover point where 0.1 A/cm2 accumulated less water than 1.5 A/cm2. The higher the temperature, the longer the time required to reach this crossover point. Results from the current density analysis showed a minimization of water slugs at 1.5 A/cm2, while the temperature analysis showed unexpectedly that, independent of current density, the condition with lowest water volume was always 35°C.

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In-Situ and Ex-Situ Investigation of Lateral Current Density Variations in a PEM Fuel Cell With Serpentine Flow Field

Volume 6: Emerging Technologies: Alternative Energy Systems; Energy Systems: Analysis, Thermodynamics and Sustainability ◽

10.1115/imece2009-12941 ◽

2009 ◽

Author(s):

Andrew Higier ◽

Hongtan Liu

Keyword(s):

Fuel Cell ◽

Flow Field ◽

Contact Resistance ◽

Current Density ◽

Pem Fuel Cell ◽

Gas Diffusion ◽

Operating Conditions ◽

Ex Situ ◽

Serpentine Flow Field

One of the most common types of flow field designs used in proton exchange membrane (PEM) fuel cell is the serpentine flow field. It is used for its simplicity of design, its effectiveness in distributing reactants and its water removal capabilities. The knowledge about where current density is higher, under the land or the channel, is critical for flow field design and optimization. Yet, no direct measurement data are available for serpentine flow fields. In this study a fuel cell with a single channel serpentine flow field is used to separately measure the current density under the land and channel on the cathode. In this manner, a systematic study is conducted under a wide variety of conditions and a series of comparisons are made between land and channel current density. Results show that under most operating conditions, current density is higher under the land than that under the channel. However, at low voltage, a rapid drop off in current density occurs under the land due to concentration losses. In order to investigate the cause of the variations of current density under the land and channel and series of ex-situ and in-situ experiments were conducted. In the ex-situ portion of the study, the contact resistance between the gas diffusion electrode (GDE) and the graphite flow plate were measured using an ex-situ impedance spectroscopy technique. The values of the contact resistance under the channel were found to be larger than that under the land. This implies that the contact resistance under the land and channel vary greatly, likely due to variations in compression under different section of the flow field. These variations in turn cause current density variations under the land and channel.

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Spatially resolved optical measurements of water partial pressure and temperature in a PEM fuel cell under dynamic operating conditions

Journal of Power Sources ◽

10.1016/j.jpowsour.2006.06.073 ◽

2006 ◽

Vol 162 (1) ◽

pp. 286-293 ◽

Cited By ~ 29

Author(s):

S. Basu ◽

M.W. Renfro ◽

B.M. Cetegen

Keyword(s):

Fuel Cell ◽

Partial Pressure ◽

Pem Fuel Cell ◽

Operating Conditions ◽

Optical Measurements ◽

Spatially Resolved ◽

Dynamic Operating

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

Journal of Fuel Cell Science and Technology ◽

10.1115/1.2349531 ◽

2006 ◽

Vol 3 (4) ◽

pp. 464-476 ◽

Cited By ~ 9

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.

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Investigation of NiFe-Based Catalysts for Oxygen Evolution in Anion-Exchange Membrane Electrolysis

Energies ◽

10.3390/en13071720 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1720

Author(s):

Sabrina Campagna Zignani ◽

Massimiliano Lo Faro ◽

Stefano Trocino ◽

Antonino Salvatore Aricò

Keyword(s):

Single Cell ◽

Anion Exchange ◽

Oxygen Evolution ◽

Current Density ◽

Electrochemical Behaviour ◽

Stress Test ◽

Supporting Electrolyte ◽

Anion Exchange Membrane ◽

Operating Conditions ◽

Exchange Membrane

NiFe electrodes are developed for the oxygen evolution reaction (OER) in an alkaline electrolyser based on an anion exchange membrane (AEM) separator and fed with diluted KOH solution as supporting electrolyte. This study reports on the electrochemical behaviour of two different NiFe-oxide compositions (i.e., Ni1Fe1-oxide and Ni1Fe2-oxide) prepared by the oxalate method. These catalysts are assessed for single-cell operation in an MEA including a Sustainion™ anion-exchange membrane. The electrochemical polarization shows a current density of 650 mA cm−2 at 2 V and 50 °C for the Ni1Fe1 anode composition. A durability test of 500 h is carried out using potential cycling as an accelerated stress-test. This shows a decrease in current density of 150 mA cm−2 mainly during the first 400 h. The performance achieved for the anion-exchange membrane electrolyser single-cell based on the NiFeOx catalyst appears promising. However, further improvements are required to enhance the stability under these operating conditions.

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

Journal of Fuel Cell Science and Technology ◽

10.1115/1.3211097 ◽

2010 ◽

Vol 7 (4) ◽

Cited By ~ 3

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.

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Experimental Results of a PEM System Operated on Hydrogen and Reformate

Journal of Fuel Cell Science and Technology ◽

10.1115/1.2784324 ◽

2008 ◽

Vol 5 (1) ◽

Cited By ~ 4

Author(s):

M. Minutillo ◽

E. Jannelli ◽

F. Tunzio

Keyword(s):

Fuel Cell ◽

Natural Gas ◽

Large Scale ◽

Pem Fuel Cell ◽

Proton Exchange ◽

Operating Conditions ◽

Cell Performance ◽

Pure Hydrogen ◽

Test Bed ◽

Fuel Cell Performance

The main objective of this study is to evaluate the performance of a proton exchange membrane (PEM) fuel cell generator operating for residential applications. The fuel cell performance has been evaluated using the test bed of the University of Cassino. The experimental activity has been focused to evaluate the performance in different operating conditions: stack temperature, feeding mode, and fuel composition. In order to use PEM fuel cell technology on a large scale, for an electric power distributed generation, it could be necessary to feed fuel cells with conventional fuel, such as natural gas, to generate hydrogen in situ because currently the infrastructure for the distribution of hydrogen is almost nonexistent. Therefore, the fuel cell performance has been evaluated both using pure hydrogen and reformate gas produced by a natural gas reforming system.

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

Journal of Fuel Cell Science and Technology ◽

10.1115/1.2756844 ◽

2006 ◽

Vol 4 (4) ◽

pp. 468-473 ◽

Cited By ~ 11

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.

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