直接甲醇燃料电池阴极水淹诱导的局部析氢反应

项目名称： 直接甲醇燃料电池阴极水淹诱导的局部析氢反应

项目编号： No.50876065

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 叶强

作者单位： 上海交通大学

项目金额： 36万元

中文摘要： 质子交换膜燃料电池内传热、传质与电化学反应之间的耦合现象异常复杂。本课题对电池内部各传输现象之间特别是与相关寄生反应之间的耦合效应进行了研究，并获得以下的成果： 1) 对电池内部水管理和热管理之间的耦合效应进行了研究，一方面研究了工作温度对液态水分布的影响，另一方面强调了电池极板温度的不均匀分布对液态水分布的影响，并提出了二者之间应相互匹配的设计原则和运行策略。 2) 对阳极流道水淹引起的阳极局部缺氢而诱发的阴极催化层中碳载体的腐蚀现象进行了研究，着重研究了氢气在水淹区域的传输机理，同时研究了不同工作条件和物性参数对阴极碳腐蚀速率的影响。 3) 对电池在恒定电流放电且阳极侧供氢不足情况下电池内部的传输现象和电化学反应进行了研究，着重研究了阳极侧氢气的传输和消耗机理，以及该情况下电流密度和电极电势的空间分布，同时发现了该情况下阴极侧的局部析氢反应。 4) 对直接甲醇燃料电池内阴极供氧不足诱发的阳极侧局部析氢反应进行了研究，系统研究了不同阴极氧气流量对电池内部组分浓度、电流密度和电极电势的空间分布的影响。揭示了临界氧气流量下，寄生析氢反应的对阴极水淹程度变化极为敏感.

中文关键词： 燃料电池；析氢反应；碳腐蚀；水淹

英文摘要： The coupled effect between heat and mass transfer and electrochemical reactions in proton exchange membrane fuel cells is one of the hottest research topics during the past few years. In this project, we investigated and highlighted the coupled effect among different transport phenomena inside fuel cells, and the main achievements are summarized as follows: 1) We conducted research on the coupled effects between water and thermal management, and highlighted the effect of operating temperature over liquid water distribution. The importance of appropriate match between non-uniform water and temperature distribution is also highlighted. 2) We investigated the carbon corrosion phenomena of cathode catalyst layers induced by local fuel starvation in proton exchange membrane fuel cells at anode channel flooding conditions. The fundamental mechanisms of hydrogen transport within the flooding area is highlighted, and the effect of operating and material parameters over carbon corrosion rate is elaborated. 3) We investigated the transport phenomena in cells operating at galvanic and sub-stoichiometric fuel feeding conditions. The mechanisms of hydrogen depletion is emphasized, and we also observed local hydrogen evolution in the cathode catalyst layers near the anode inlet. 4) We investigated the phenomenon of spontaneous hydrogen evolution in the anode side of a direct methanol fuel cell at open-circuit and low air flow rate conditions. The effects of air flow rate over the distributions of species concentration, current density and electrode potentials are investigated, and the effect of cathode water flooding over cell behavior is also highlighted.

英文关键词： fuel cell; hydrogen evolution; carbon corrosion; flooding