质子交换膜燃料电池

因其具有独特的优点，质子交换膜燃料电池（PEMFC）的市场前景很好，国际上已经形成了一股研究开发热潮。电催化剂、质子交换膜、双极板、燃料、水管理、热管理是质子交换膜燃料电池的关键技术。文章介绍了PEMFC的特点及开发应用状况，综述了PEMFC的研究进展。     

质子交换膜燃料电池内电荷传递的数值模拟

为深入研究质子交换膜燃料电池内电荷传递的规律,发展了一个三维的单相流、非等温数学模型,模型考虑了电子在催化层和扩散层、质子在催化层和质子交换膜中的传递。通过计算得到了电池内电位和电流密度的空间分布,分析了不同电极结构参数下电流密度的分布和最终造成的性能差异。结果表明,欧姆电位的下降主要发生在膜相电位,而碳相电位的下降几乎可以忽略不计;电流密度在流道与集电极交界处出现＂火焰形＂累积效应;改变电池的结构对电池性能影响不大,应结合加工成本和电流密度分布综合考虑。     

质子交换膜燃料电池传输现象的数值分析

建立了一个具有蛇形通道,采用Nafion117膜单体质子交换膜燃料电池的三维数学模型,该模型同时考虑了流动、传热、传质、电化学动力学和多组分传输现象。通过求解传输方程组,并耦合电化学动力学方程,获得了电池的极化性能曲线和电池内部的反应物浓度、温度、速度分布。计算结果表明,增加电极孔隙率、提高电池运行温度和压力有助于改善电池性能。估算的极化性能与献中的实验数据基本符合。分析了运行条件对电池性能的影响。     

质子交换膜燃料电池阴极传质过程的数值模拟

利用CFD方法对采用交指型流道质子交换膜燃料电池阴极的传质过程进行数值模拟,得到了阴极扩散层内氧气和水蒸汽质量浓度的分布特性,探讨了电池结构参数和操作条件对电池性能的影响。     

质子交换膜燃料电池可靠性分析

可靠性是质子交换膜燃料电池(PEMFC)的重要指标，文中定性分析了PEMFC组成元件、装配工艺和工作过程的可靠性。提出了提高PEMFC可靠性的措施和可靠性的设计原则。     

基于Python的质子交换膜燃料电池引射器自动仿真设计

质子交换膜燃料电池（PEMFC）引射器设计通常需经过结构参数计算、计算域建模、网格划分和数值模拟等步骤,并经过多轮迭代得到一个性能较优的设计方案,所需时间成本较高。针对PEMFC引射器,通过Python编程语言将以上功能进行集成,自动计算引射器结构参数,并调用OpenFOAM软件中的blockMesh工具进行计算域建模、网格划分,以及rhoSimpleFoam求解器进行数值仿真验证,形成一套参数化的自动仿真设计工具。研究表明,该工具可显著提高PEMFC引射器设计开发的速度,从而促进汽车工业的发展。     

质子交换膜燃料电池自增湿研究进展

概述了质子交换膜燃料电池自增湿研究状况，指出自增湿的出发点是有效利用电池阴极过程生成水。综述了薄电解质膜、新型自增湿膜、自增湿流场结构三种方法的研究进展及适用空间。对自增湿技术发展前景进行了探讨。     

质子交换膜燃料电池的开发应用

质子交换膜燃料电池（PEMFC）作为一种新一代的发电技术,已成为世界各国特别是发达国家的研发重点被纳入发展规划,应用领域从特殊应用到商品化、产业化不断开拓.但PEMFC的产业化和推广应用受关键材料和工艺技术的制约,为了加速我国PEMFC的发展,今后必须投入足够的财力,组织相关学科的人才,制定可行的规划,加大科研力度.     

质子交换膜燃料电池的研发动态

质子交换膜燃料电池(PEMFC)因其独特的优点具有很好的市场前景,国际上已经形成了一种研究热潮.电催化剂、质子交换膜、双极板、燃料、水管理、热管理是其关键技术.文章介绍了PEMFC的特点及开发应用状况,综述了PEMFC的研究进展.     

质子交换膜燃料电池的应用研究

质子交换膜燃料电池（PEMFC）与其它燃料电池一样，是利用氧化、还原反应产生电子流的装置。它以氢为燃料、以氧为氧化剂，把化学能直接转化为电能。由于该电池以氢气为燃料，生成的产物是水，对环境造成的污染少。在化石燃料日益短缺及环境污染日益严峻的条件下，燃料电池倍受关注。而近几年发展起来的质子交换膜燃料电池（PEMFC）由于其无污染、发电效率高等特点正受到各国各部门的重视。主要评述了PEMFC的主要用途、工作原理及其实现商业化所面临的几个主要问题。     

PEMFC系统引射器设计及仿真研究

针对燃料电池汽车的运行特点,对氢气循环引射器进行了结构设计,利用Fluent软件对所设计的引射器进行了全工况模拟,确定了对引射器效率影响较大的变量。通过改变工作流体流量,并经过多次模拟后发现,为了使氢气引射器在怠速工况下不失效,引射器前端工作流体压力p_p要≥1.05 MPa。分析了工作流体质量流量G_p、喷嘴喉部直径d_(p*)和工作流体压力p_p对引射性能的影响,发现G_p对引射器的引射性能影响最大,并给出了G_p的取值范围。研究建议引射器设计时G_p在0.21~0.23 g·s~(-1)范围内最佳。     

Characteristic simulation and numerical investigation of membrane electrode assembly in proton exchange membrane fuel cell

This study analyzes the characteristic numerical analysis of membrane electrode assembly in Proton Exchange Membrane Fuel Cell (PEMFC) with bipolar plate, flow channel, gas diffusion electrode, and proton exchange membrane. The numerical solution focuses on discussing the effects of different parameters, including permeability, porosity, and operation voltage, on various mass fractions, current-voltage curve, and power-voltage curve.The results show that as the porous medium with high gas permeability is an important factor that affects the mass fraction of hydrogen. Regarding the analyses of various porosities, the fuel cell performance can be effectively promoted with larger ratio of porosity and permeability. However, increasing the porosity will affect the electrical conductivity and increase the flooding of water, which will block the flow channel and reduce efficiency.     

基于电化学阻抗法的质子交换膜燃料电池“三步活化法”机理研究

活化能够有效地发挥质子交换膜燃料电池膜电极的性能,"三步活化法"是其中一种比较理想的方法。为了研究"三步活化法"活化质子交换膜燃料电池的机理,利用电化学阻抗谱测试"三步活化法"过程中的膜电极阻抗,并建立等效电路模型拟合所得实验数据。结果表明,"三步活化法"可以有效降低欧姆阻抗、阳极法拉第阻抗、阴极法拉第阻抗以及阴极传质阻抗,这表明"三步活化法"有利于电子、质子、气体与水的传输通道的形成。     

质子交换膜燃料电池故障检测研究

针对质子交换膜燃料电池(PEMFC)发电系统的故障检测和系统稳定性问题,结合其多传感器特性,采用基于实时PCA的质子交换膜燃料电池故障检测方法,根据燃料电池反应信号数据建立PCA模型,通过窗口过滤方式和遗忘因子算法实时更新模型,并将降维后获得的数据用统计方法进行处理,从而检测出故障。有效地简化了燃料电池系统故障检测的过程,改善了故障检测的实时性,提高了燃料电池系统工作的稳定性和可靠性。     

Influence of anisotropic gas diffusion layers on transport phenomena in a proton exchange membrane fuel cell

The gas diffusion layer is an anisotropic porous medium, which provides pathways for the reactant gases and produced water, conducts the electrical current, removes the generated heat, and provides mechanical support. However, the gas diffusion layer is mostly considered as isotropic in numerical simulations. In the present study, a three‐dimensional, two‐phase flow, and non‐isothermal agglomerate model with consideration of anisotropic permeability, mass diffusivity, thermal conductivity, and electrical conductivity was developed and employed to investigate effects of anisotropic properties on the transport phenomena in a proton exchange membrane fuel cell. The temperature of the anisotropic case is less than that of the isotropic case, and the temperature difference increases with increasing current density. Furthermore, the distributions of the oxygen mass fraction, liquid water saturation, water content, and local current density for both cases are also compared and discussed in detail. The cell performance is over‐predicted by the isotropic model, and the current density of the isotropic case is greater than that of the anisotropic case by approximately 10% at an operating cell voltage of 0.3 V. Both the local transport characteristics and overall cell performance are different for the isotropic and anisotropic cases. Accordingly, it is concluded that the anisotropic properties of the gas diffusion layer must be taken into account in the mathematical model. Copyright © 2017 John Wiley & Sons, Ltd.     

Carbon monoxide poisoning of proton exchange membrane fuel cells

Proton exchange membrane fuel cell (PEMFC) performance degrades when carbon monoxide (CO) is present in the fuel gas; this is referred to as CO poisoning. This paper investigates CO poisoning of PEMFCs by reviewing work on the electrochemistry of CO and hydrogen, the experimental performance of PEMFCs exhibiting CO poisoning, methods to mitigate CO poisoning and theoretical models of CO poisoning. It is found that CO poisons the anode reaction through preferentially adsorbing to the platinum surface and blocking active sites, and that the CO poisoning effect is slow and reversible. There exist three methods to mitigate the effect of CO poisoning: (i) the use of a platinum alloy catalyst, (ii) higher cell operating temperature and (iii) introduction of oxygen into the fuel gas flow. Of these three methods, the third is the most practical. There are several models available in the literature for the effect of CO poisoning on a PEMFC and from the modeling efforts, it is clear that small CO oxidation rates can result in much increased performance of the anode. However, none of the existing models have considered the effect of transport phenomena in a cell, nor the effect of oxygen crossover from the cathode, which may be a significant contributor to CO tolerance in a PEMFC. In addition, there is a lack of data for CO oxidation and adsorption at low temperatures, which is needed for detailed modeling of CO poisoning in PEMFCs. Copyright © 2001 John Wiley & Sons, Ltd.     

质子交换膜燃料电池双极板的设计与模拟分析

质子交换膜燃料电池是直接将化学能转换为电能的装置,双极板上的流道结构对燃料电池的工作性能具有较大的影响。根据应用要求设计了具有平行流道、蛇形流道及希尔伯特分形流道的双极板结构,模拟计算了氢气在不同类型的流道和气体扩散层中的分布状态,分析了燃料电池的输出电流密度和功率密度随电极间电压的变化特点,比较了不同的流道结构对燃料电池输出电流密度的影响,以及不同的工作温度及气体压强的情况下,燃料电池输出电流密度随温度及压强的变化规律。