Enhancement of water management in PEM fuel cells

加强 PEM 燃料电池的水管理

• 批准号: 341873-2007
• 负责人: Hoorfar, Mina
• 金额: $ 1.24万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=482332
• 关键词: Enhancement; water; management; PEM; fuel

In the past century, there has been a dramatic climate change due to the greenhouse effect mainly caused by increased levels of carbon dioxide released into the atmosphere. Also, despite public awareness through extensive media coverage, emissions from industry and motor vehicles are still the main cause of air pollution that claims thousands of lives in Canada every year according to Health Canada. The primary cause of both climate change and air pollution is the burning of fossil fuels. In view of these problems, alternative sources of energy must be explored. Proton exchange membrane (PEM) fuel cells have drawn much attention in the last decade as a high-efficiency and low-emission source of energy. However, the performance and cost of the PEM fuel cells must be improved significantly before they can constitute a viable market. One of the major problems of the current PEM fuel cells is water management. The polymer membrane of the PEM fuel cell needs to be well hydrated to maintain proton conductivity. However, excessive water vapor condensation, due to a long operation or large output current, forms micro-droplets that block the access of the reactant gas to the reaction site. The improvement of water management requires the study of droplet formation and liquid water transport in the internal network of the fuel cell. The proposed research program involves the study of three mechanisms: 1) micro-droplet formation on different layers of the membrane electrode assembly (MEA), 2) liquid water transport in the gas diffusion layer (GDL), and 3) droplet agglomeration at the GDL/flow channel interface. To gain better insight into these mechanisms, it is required to determine the effect of interfacial and capillary forces on droplet formation and liquid transport in the PEM fuel cell. Experimental methodologies will be developed under this research program to determine 1) the local interfacial properties of the micro-droplets in the MEA, 2) the wettability of the GDL, and 3) the interfacial properties of the droplets at the GDL/flow channel interface. This work will result in the enhancement of water management in the PEM fuel cells and hence contribute to the strengthening of Canadian fuel cell technology.

在过去的世纪里，由于温室效应，主要是由于释放到大气中的二氧化碳水平增加而引起的，气候发生了急剧变化。此外，尽管通过广泛的媒体报道提高了公众的认识，但根据加拿大卫生部的数据，工业和机动车辆的排放仍然是空气污染的主要原因，每年在加拿大造成数千人死亡。气候变化和空气污染的主要原因是化石燃料的燃烧。鉴于这些问题，必须探索替代能源。质子交换膜（PEM）燃料电池作为一种高效率、低排放的能源，在过去的十年里引起了人们的广泛关注。然而，PEM燃料电池的性能和成本必须得到显着改善，才能构成一个可行的市场。当前PEM燃料电池的主要问题之一是水管理。PEM燃料电池的聚合物膜需要很好地水合以保持质子传导性。然而，由于长时间的操作或大的输出电流，过多的水蒸气冷凝形成微滴，其阻挡反应物气体进入反应部位。水管理的改进需要研究燃料电池内部网络中液滴的形成和液态水的传输。提出的研究计划涉及三个机制的研究：1）微滴形成的不同层的膜电极组件（MEA），2）液体水传输的气体扩散层（GDL），和3）液滴凝聚在GDL/流动通道接口。为了更好地了解这些机制，需要确定界面和毛细管力对PEM燃料电池中液滴形成和液体传输的影响。实验方法将根据本研究计划开发，以确定1）MEA中微液滴的局部界面特性，2）GDL的润湿性，以及3）GDL/流道界面处液滴的界面特性。这项工作将导致在PEM燃料电池的水管理的加强，从而有助于加强加拿大的燃料电池技术。