Interfaces and Related Losses in PEM Fuel Cells: Theoretical and Experimental Studies

PEM 燃料电池中的界面和相关损耗：理论和实验研究

• 批准号: 1066623
• 负责人: Emin Caglan Kumbur
• 金额: $ 35.83万
• 依托单位: Drexel University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1066623&HistoricalAwards=false
• 关键词: Interfaces; Related; Losses; PEM; Fuel

1066623 PI KumburThe objective of this work is to define a scientific framework that enables detailed assessment of the interfacial morphology and interfacial transport mechanisms on the of the polymer electrolyte fuel cell (PEFCs). The PIs hypothesize that a major reason for many shortcomings of current model is the treatment of the interface as an infinitely thin layer, having perfect contact and homogenous properties. Preliminary work by PIs demonstrates that the micro-porous layer (MPL) and catalyst layer (CL) surfaces are not smooth; instead they exhibit surface irregularities, such as elongated surface cracks, holes, and dents. These surface features result in imperfect interfaces, which promote performance loss an. Compelling evidence suggests that interfacial regions are of importance in fuel-cell performance, but a fundamental understanding of the role of these critical regions is still lacking. The PIs will address this issue and perform a verification of the impact of the interface on the performance and durability of PEFCs. To achieve this, the PIs will carry out a combined experimental and computational plan, including: 1) ex-situ and in-situ measurements of a broad range of interfacial transport properties and water retention characteristics using advanced diagnostic tools and neutron imaging, 2) digital characterization of the bonded interface structure through a combined optical profilometry and dual-beam focused ion-beam scanning electron microscope study, 3) development of a validated interfacial contact model ( adapting well-established frameworks from tribology) to create a set of cloned virtual MPL/CL interface structures under compression, and 4) using these virtual interfaces, develop multi-scale transport and performance models to describe the impact of these interface regions on the mass, thermal and electrical transport characteristics of PEFCs.Intellectual Merit: This approach will enable higher fidelity modeling capability with realistic interfacial morphology and interfacial transport. This project will not only have a substantial impact on the engineering of novel materials for high performance, but also will provide significant guidance for durability studies. The proposed methodology also has a strong transformative nature as it will bring a new perspective to approach the interface related performance and durability issues in PEFCs and other types of fuel cells. The proposed methodology for characterizing the interface will be transformable to other fields, as it can be further extended into other electrochemical systems (e.g., Li-ion and other batteries) to help us address similar fundamental gaps.Broader Impact: Specific activities will include: i) training of graduate and undergraduate students in multidisciplinary engineering fields, ii) formation of a yearly graduate student exchange between labs at Drexel and Carnegie Mellon (CMU), iii) development of new instructional materials for fuel cell courses taught at Drexel and CMU, iv) active recruitment and training of women and underrepresented minority engineers by leveraging the established programs (REU, IGERT, GAANN, LSAMP) at Drexel and CMU, v) training of local high school students through Drexel Mentorship Program, vi) hosting local high school teachers through Drexel-Penn NanoRET program to develop educational modules related to alternative energy, vii) semi-annual workshops for high school teachers as a part of the ?What is Engineering? program at CMU, and viii) presentation of results in publications and PIs? websites for broader dissemination.

1066623 PI Kumbur这项工作的目的是定义一个科学的框架，能够详细评估聚合物电解质燃料电池（PEFC）的界面形态和界面传输机制。PI假设当前模型的许多缺点的主要原因是将界面处理为无限薄层，具有完美的接触和均匀的特性。PI的初步工作表明，微孔层（MPL）和催化剂层（CL）表面并不光滑;相反，它们表现出表面不规则性，如细长的表面裂纹、孔洞和凹痕。这些表面特征导致不完美的界面，这促进了性能损失，令人信服的证据表明，界面区域是重要的燃料电池的性能，但这些关键区域的作用仍然缺乏一个基本的理解。 PI将解决这一问题，并验证接口对PEFC性能和耐久性的影响。为了实现这一目标，PI将执行一个综合的实验和计算计划，包括：1）使用先进的诊断工具和中子成像对广泛的界面传输特性和保水特性进行非原位和原位测量，2）通过组合的光学轮廓测量和双束聚焦离子束扫描电子显微镜研究对结合的界面结构进行数字表征，3）开发经验证的界面接触模型（从摩擦学中改编成熟的框架）来创建一组压缩下的克隆虚拟MPL/CL界面结构，以及4）使用这些虚拟界面，开发多尺度传输和性能模型来描述这些界面区域对PEFC的质量、热和电传输特性的影响。这种方法将使逼真的界面形态和界面传输更高保真的建模能力。该项目不仅将对高性能新型材料的工程产生重大影响，而且将为耐久性研究提供重要指导。所提出的方法也具有很强的变革性，因为它将带来一个新的视角来处理PEFC和其他类型的燃料电池中与界面相关的性能和耐久性问题。所提出的用于表征界面的方法将可转换到其他领域，因为它可以进一步扩展到其他电化学系统（例如，更广泛的影响：具体活动将包括：i）在多学科工程领域培训研究生和本科生，ii）在德雷克塞尔和卡内基梅隆大学（CMU）的实验室之间形成每年一次的研究生交流，iii）为德雷克塞尔和卡内基梅隆大学教授的燃料电池课程开发新的教学材料，iv）通过利用既定方案，积极招聘和培训妇女和代表性不足的少数民族工程师（REU，IGERT，GAANN，LSAMP）在德雷克塞尔和CMU，v）通过德雷克塞尔导师计划培训当地高中学生，vi）通过德雷克塞尔-宾夕法尼亚大学纳米可再生能源项目接待当地高中教师，开发与替代能源有关的教育模块，（七）每半年为高中教师举办一次讲习班，作为《教育法》的一部分。什么是工程学？计划在CMU，和八）在出版物和PI的结果介绍？网站进行更广泛的传播。