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91.
系统总结了质子交换膜燃料电池(PEMFC)用催化剂的种类,以及其在长时间运行过程中性能衰减的主要原因,归纳了近年来提高催化剂稳定性的改进方法,包括改变合金组成、对催化剂表面进行修饰、选择高稳定性催化剂载体、制备新型催化剂材料;最后提出了该催化剂材料研究中存在的问题和今后的发展方向。 相似文献
92.
In this paper, an electrochemical‐based proton exchange membrane fuel cell (PEMFC) model suitable for engineering applications is presented. In order to improve the accuracy of this model so that it can reflect the actual PEMFC performance better, its parameters are optimized by means of a modified particle swarm optimization (MPSO). The MPSO is a modified method for the PSO's inertia weight. The proposed inertia weight is calculated according to the distance of the particle's current position from the best solution of the entire swarm. The obtained results of the PEMFC model with optimized parameters agree with experimental data well. Therefore, the MPSO is a helpful and reliable technique for optimizing the model parameters and can be used to solve other complex parameter optimization problems of fuel cell models. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
93.
Badreddine Larbi Wael AlimiRidha Chouikh Amenallah Guizani 《International Journal of Hydrogen Energy》2013
This paper presents a numerical modeling, provides an improved understanding of the fundamental transport phenomena inside the PEM fuel cell. The problem is stated in a steady-state, two-dimensional model and Cartesian coordinates system by using a single domain and a control volume method. The model consists of non-linear, coupled partial differential equations representing the conservation of mass, momentum, species, charges and energy with electrochemical reactions that are valid for gas diffusion electrodes, catalyst layers and membrane region. The modeling of bidirectional, non-isothermal and steady problem of PEMFC provides results concerning the species fraction, potential and temperature distribution in different domain. 相似文献
94.
Generally, multi-phase models for the proton exchange membrane fuel cell (PEMFC) that seek to capture the local transport phenomena are inherently non-linear with high computational overhead. We address the latter with a reduced multi-phase, multicomponent, and non-isothermal model that is inexpensive to compute without sacrificing geometrical resolution and the salient features of the PEMFC - this is accomplished by considering a PEMFC equipped with porous-type flow fields coupled with scaling arguments and leading-order asymptotics. The reduced model is verified with the calibrated and validated full model for three different experimental fuel cells: good agreement is found. Overall, memory requirements and computational time are reduced by around 2-3 orders of magnitude. In addition, thermal decoupling is explored in an attempt to further reduce computational cost. Finally, we discuss how other types of flow fields and transient conditions can be incorporated into the mathematical and numerical framework presented here. 相似文献
95.
Belgin BozbiyikValery A. Danilov Joeri Denayer 《International Journal of Hydrogen Energy》2011,36(22):14552-14561
This study presents an improved Tank in Series Reactor (TSR) Proton Exchange Membrane (PEM) fuel cell model with mass and energy balance equations accounting for evaporation and condensation in cathode channels. The TSR model includes the modified charge balance equation suitable for potentiostatic fuel cell operation mode. Polarization curves calculated with the improved model agree with experimental data from the literature. The developed TSR model is able to predict the limiting two-dimensional profiles in PEMFC. Simulation results illustrate the influence of co-current and counter current mode on PEM fuel cell performance. 相似文献
96.
G. Giacoppo O. BarberaA. Carbone I. GattoA. Saccà R. PediciniE. Passalacqua 《International Journal of Hydrogen Energy》2013
In this work, the performance of a High Temperature (HT) Polymer Electrolyte Fuel Cell (PEFC) stack for co-generation application was investigated. A 3 kW power unit composed of two 1.5 kW modules was designed, manufactured and tested. The module was composed of 40 composite graphite cell with an active area of 150 cm2. Composite Membrane Electrode Assemblies (MEAs) based on Nafion/Zirconia membranes were used to explore the behavior of the stack at high temperature (120 °C). Tests were performed in both pure Hydrogen and H2/CO2/CO mixture at different humidification grade, simulating the exit gas from a methane fuel processor. The fuel cells stack has generated a maximum power of 2400 W at 105 A with pure hydrogen and fully hydrated gases and 1700 W at 90 A by operating at low humidity grade (95/49 RH% for H2/Air). In case the stack was fed with reformate simulated stream fully saturated, a maximum power of 2290 W at 105 A was reached: only a power loss of 5% was recorded by using reformate stream instead of pure hydrogen. The humidification grade of Nafion membrane was indicated as the main factor affecting the proton conductivity of Nafion while the addition of the inert compound like YSZ, did not affectthe electrochemical properties of the membrane but, rather has enhanced mechanical resistance at high temperature. 相似文献
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99.
聚合物电解质燃料电池研究进展 总被引:1,自引:0,他引:1
综述了聚合物电解质燃料电池(PEMFC)的研究进展,讨论了PEMFC的五个主要研究问题,比较、分析了Nafion、聚苯并咪唑(PBI)膜和其他质子交换膜性能。最后,对质子交换膜的研究提供了意见。 相似文献
100.
质子交换膜燃料电池的研究开发及应用新进展 总被引:12,自引:0,他引:12
介绍了国内外研究质子交换膜燃料电池的整体现状及水平 ,从电催化剂、膜电极及其制备工艺、质子交换膜以及双极板等几个方面 ,综述了质子交换膜燃料电池在材料及部件方面取得的成绩及研究现状 ,概述了质子交换膜燃料电池目前在电动车、船舶、移动电源等方面的应用情况。提出了我国质子交换膜燃料电池的发展方向 相似文献