Computer-aided design of catalyst layers for polymer electrolyte fuel cells

聚合物电解质燃料电池车辆预计将降低从井到轮的能量消耗，并减少绿色室内气体和其他空气污染物的排放。 目前这一代燃料电池汽车已经展示了客户期望的所有性能属性，例如长距离，快速加油和冷启动。然而，燃料电池仍然过于昂贵，无法成功商业化。燃料电池成本的主要贡献者之一是燃料电池电极内使用的铂。 实验研究表明，功能梯度和微结构电极提供了一个很好的机会，以减少燃料电池铂负载，而不会产生负面影响的性能。然而，燃料电池电极只有几微米厚;因此，需要数学模型来理解电极内部发生的物理过程，以改进其设计。大多数电极数学模型将电极视为宏观均匀层，从而不能适当地解释电极中的局部中尺度质量传输损失。 拟议的研究将开发重建和网格化算法，以及数学模型，以更准确地研究在异质和结构工程电极中发生的介观质量传输和电化学反应。由于这些新型电极将需要与燃料电池中的其他组件集成，并且这些组件影响电极的水，热和反应物平衡，因此还将研究集成介观尺度和宏观尺度燃料电池模型的数值多尺度方法。 介观尺度和多尺度模型将用于功能梯度电极的计算机辅助设计。将对这些电极进行制造和测试，以评估分析和设计框架的有效性。AFCC还将使用所提出的多尺度数学模型来开发新颖的分层结构电极。最成功的电极将集成在下一代燃料电池汽车中。目前的项目还将有助于培训6名高素质人员。

Polymer electrolyte fuel cell vehicles are anticipated to lower well-to-wheel energy consumption, and reduce emissions of green house gases and other air pollutants. The current generation of fuel cell vehicles have demonstrated all the performance attributes that customers expect, such as long range, fast re-fuelling and cold start. However, the fuel cells are still too costly to enable its successful commercialization. One of the major contributors to fuel cell costs is the platinum used inside the fuel cell electrodes. Experimental research has shown that functionally-graded and micro-structured electrodes present a great opportunity to reduce fuel cell platinum loading without negatively impacting performance. Fuel cell electrodes however are several micro-meters thick; therefore, mathematical models are required to understand the physical process occurring inside the electrode in order to improve their design. Most electrode mathematical models treat the electrode as a macro-homogeneous layer, thereby not appropriately accounting for local meso-scale mass transport losses in the electrodes. The proposed research will develop reconstruction and meshing algorithms, and mathematical models to more accurately study the meso-scale mass transport and electrochemical reactions occurring in heterogeneous and structurally engineered electrodes. Since these novel electrodes will need to be integrated with the other components in a fuel cell and such components affect the water, thermal and reactant balance of the electrode, numerical multi-scale methods that integrate meso-scale and macro-scale fuel cell models will also be studied. Meso-scale and multi-scale models will be used for computer-aided design of functionally-graded electrodes. These electrodes will be fabricated and tested to assess the validity of the analysis and design framework. AFCC will also use the proposed multi-scale mathematical models to develop novel hierarchically structured electrodes. The most successful electrodes will be integrated in their next generation fuel cell vehicles. The current project will also contribute to the training of six highly qualified personnel.