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Investigation of a Micro PEM Fuel Cell Pack Based on MEMS Technology
Tao Wang, Xigui Zhang, Jian Zhang, Dan Zheng, Cong Chen, Xinxin Li, Chuanzheng Yang and Baojia XiaV-I
The Open Fuels & Energy Science Journal , 2008, DOI: 10.2174/1876973X00801010046]
Abstract: Investigation of a micro PEM fuel cell pack based on MEMS technology is carried out in this paper. A Novel type of Z-type anode flow field plates were applied to replace the full pin-type ones used previously and all the single cells were assembled in the same plane with a fuel distributor as their support. The total pack’s volume is about 4.0ml. Operating on dry H2 and air-breathing conditions at 20±3°C and 50±3% RH, the pack produced the peak power of 1.34W and the estimated maximum power density of the pack could reach 335W/L. Meanwhile, all the single cells had rather even performances which were based on V-I and internal resistance measurement (EIS). The results suggested that the pack’s performance was greatly improved compared to the previous work. The novel Z-type anode flow field leading to more even fuel distribution among each cell probably had the greatest contribution for the improvement.
Performance optimization of a PEM hydrogen-oxygen fuel cell  [PDF]
Maher A.R. Sadiq Al-Baghdadi
International Journal of Energy and Environment , 2013,
Abstract: The objective was to develop a semi-empirical model that would simulate the performance of proton exchange membrane (PEM) fuel cells without extensive calculations. A fuel cell mathematical module has been designed and constructed to determine the performance of a PEM fuel cell. The influence of some operating parameters on the performance of PEM fuel cell has been investigated using pure hydrogen on the anode side and oxygen on the cathode side. The present model can be used to investigate the influence of process variables for design optimization of fuel cells, stacks, and complete fuel cell power system. The possible mechanisms of the parameter effects and their interrelationships are discussed. In order to assess the validity of the developed model a real PEM fuel cell system has been used to generate experimental data. The comparison shows good agreements between the modelling results and the experimental data. The model is shown a very useful for estimating the performance of PEM fuel cell stacks and optimization of fuel cell system integration and operation.
Sensibility study of flooding and drying issues to the operating conditions in PEM fuel cells  [PDF]
F. Breque, J. Ramousse, Y. Dub, K. Agbossou, P. Adzakpa
International Journal of Energy and Environment , 2010,
Abstract: Due to water management issues, operating conditions need to be carefully chosen in order to properly operate fuel cells. Because of the gas consumption along the feeding channels and water production at the cathode, internal cell humidification is highly inhomogeneous. Consequently, operating fuel cells are very often close to critical operating conditions, such as flooding and drying, at least locally. Based on this observation, the critical current, corresponding to internal cell humidification balance (acurate membrane hydration, without excess of water at the electrodes), is deduced from a pseudo-2D model of mass transfer in the cell. Using the model, a parametric sensibility study of the operating conditions is presented to analyze the cell internal humidification. Dead-end and flow-through modes of hydrogen supply are also compared. It is shown that the operating temperature is a key parameter to manage the cell humidification. Moreover, although the oxygen stoichiometric ratio has an effect on cell humidification, this influence is limited and cannot be used alone to adjust the cell humidification. Furthermore, it is shown that in some cases, humidifying the anode inlet gas is of little interest to the internal humidification adjustment. Finally, those results allow to understand the role that each operating parameter can play on the cell internal humidification. Consequently, this study is of a great interest to water management improvement in polymer electrolyte membrane fuel cells.
Experimental and Numerical Study on the Cold Start Performance of a Single PEM Fuel Cell  [PDF]
Calvin H. Li,G. P. Peterson
Advances in Mechanical Engineering , 2010, DOI: 10.1155/2010/403816
Abstract: A combined experimental and analytical investigation of single proton exchange membrane (PEM) fuel cells, during cold start, has been conducted. The temperature influence on the performance of a single PEM fuel cell and the cold start failure of the PEM fuel cell was evaluated experimentally to determine the failure mechanisms and performance. The voltage, current, and power characteristics were investigated as a function of the load, the hydrogen fuel flow rate, and the cell temperature. The characteristics of cold start for a single PEM fuel cell were analyzed, and the various failure mechanisms were explored and characterized. In an effort to better understand the operational behavior and failure modes, a numerical simulation was also developed. The results of this analysis were then compared with the previously obtained experimental results and confirmed the accuracy of the failure mechanisms identified.
Optimization of Proton Exchange Membrane Fuel Cell at Different operating and design Variables Using Genetic Algorithm
Narender Kumar,,Purnima Swarup Khare,,Abhay Swarup
International Journal of Engineering Science and Technology , 2010,
Abstract: In Proton Exchange Membrane fuel cell the operating condition and design variable plays very important role for improving the performance. This work focused on numerical simulation of the effects operating conditions and design variables, especially temperature, pressure, sticheometry of the reactant gases, area of the cell andmembrane thickness. To investigate the effect of the operating onditions and design variables on the fuel cell performance, in this study we have set temperature;313K Keywords Design Variables --- Operating Variables --- Output Voltage --- Proton Exchange Membrane (PEM) Fuel Cell
Environmental Impact of High Altitudes on the Operation of PEM Fuel Cell Based UAS  [PDF]
Ibrahim M. Saleh, Rashid Ali, Hongwei Zhang
Energy and Power Engineering (EPE) , 2018, DOI: 10.4236/epe.2018.103007
Abstract: Fuel cell is a device that converts the chemical energy in the reactants into the electrical energy after steps of sequential electrochemical processes with no significant impact on the environment. For high altitude long endurance (HALE) of unmanned aircraft system (UAS) where fuel cell operates as a prime source of power, the operation and performance of a PEM fuel cell at different level of altitudes is vitally important. In this paper, the impact of direct using extracted air from high altitudes atmosphere in order to feed the stack is investigated, and the governing equations of the supplied air and oxygen to the PEM fuel cell stack are developed. The impact of high altitudes upon the operation and the consumption of air are determined in order to maintain certain level of delivered power to the load. Also the implications associated with operating the PEM fuel cell stack at high altitudes and different technical solutions are proposed. Various modes of Integral, Proportional-Integral, and Proportional-Integral-Derivative controller are introduced and examined for different time setting responses in order to determine the most adequate trade-off choice between fast response and reactants consumption which provides the necessary optimization of the air consumption for the developed model of PEM fuel cell used for UAS operation.
PEM Fuel Cells - Fundamentals, Modeling and Applications
Maher A.R. Sadiq Al-Baghdadi
International Journal of Energy and Environment , 2013,
Abstract: Part I: Fundamentals Chapter 1: Introduction. Chapter 2: PEM fuel cell thermodynamics, electrochemistry, and performance. Chapter 3: PEM fuel cell components. Chapter 4: PEM fuel cell failure modes. Part II: Modeling and Simulation Chapter 5: PEM fuel cell models based on semi-empirical simulation. Chapter 6: PEM fuel cell models based on computational fluid dynamics. Part III: Applications Chapter 7: PEM fuel cell system design and applications.
Determination of Combustion Parameters of a PEM Fuel Cell at Various Combustion Conditions
Ayoub Kazim
Journal of Engineering and Applied Sciences , 2012,
Abstract: This study evaluates the parameters that are associated with a combustion process of a Proton Exchange Membrane (PEM) fuel cell at various combustion conditions. Combustion parameters such as adiabatic flame temperature, air-fuel ratio, and fraction of water that condenses at 25 C and 1 atm, are considered in the analysis, which is performed at a theoretical air ratio ranging from 100 to 300% (from 0 to 200% excess air). Furthermore, exergy destruction associated with the combustion process was evaluated at each specified condition. The calculated results illustrated that the adiabatic flame temperature reached a maximum value of 2,526 K at 100% theoretical air and then reduced to 1,270 K at a theoretical air of 300%. Conversely, exergy destruction was evaluated to be 53,236 and 96,949 kJ kmol 1 at 100 and 300% of theoretical air, respectively.
Optimal design of PEM fuel cells to generate maximum power: A CFD study  [PDF]
Maher A.R. Sadiq Al-Baghdadi
International Journal of Energy and Environment , 2011,
Abstract: A full three-dimensional, multi-phase computational fluid dynamics model of a PEM fuel cell has been developed. The parametric study using this model has been performed and discussed in detail. Optimization study of a PEM fuel cell performance has been performed. The study quantifies and analyses the impact of operating, design, and material parameters on fuel cell performance and get an optimal design for PEM fuel cells to generate maximum power. To generate maximum power, the results show that the cell must be operate at higher cell operating temperature, higher cell operating pressure, higher stoichiometric flow ratio, and must have higher GDL porosity, higher GDL thermal conductivity, narrower gases channels, and thinner membrane. At these optimum conditions, the result shows that the total displacement and the degree of the deformation inside the MEA were decreased. However, the Miss stress in the membrane was increased due to higher cell operating temperature.
Dynamic Response during PEM Fuel Cell Loading-up  [PDF]
Pucheng Pei,Xing Yuan,Jun Gou,Pengcheng Li
Materials , 2009, DOI: 10.3390/ma2030734
Abstract: A study on the effects of controlling and operating parameters for a Proton Exchange Membrane (PEM) fuel cell on the dynamic phenomena during the loading-up process is presented. The effect of the four parameters of load-up amplitudes and rates, operating pressures and current levels on gas supply or even starvation in the flow field is analyzed based accordingly on the transient characteristics of current output and voltage. Experiments are carried out in a single fuel cell with an active area of 285 cm2. The results show that increasing the loading-up amplitude can inevitably increase the possibility of gas starvation in channels when a constant flow rate has been set for the cathode; With a higher operating pressure, the dynamic performance will be improved and gas starvations can be relieved. The transient gas supply in the flow channel during two loading-up mode has also been discussed. The experimental results will be helpful for optimizing the control and operation strategies for PEM fuel cells in vehicles.
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