Abstract:

Gas diffusion layer (GDL) plays an important role in supporting the catalytic layer and providing the transmission access of gas and water in proton exchange membrane fuel cell (PEMFC). Designing and optimizing the structure of GDL significantly influence the performance of fuel cell. In this paper, the application prospect of hydrogen fuel cell and the structure and working principle of PEMFC are briefly introduced. The problem of insufficient gas-liquid transmission capacity of GDL is pointed out and the effects of pore structure, carbon material, and microstructure of microporous layer, wettability and durability on the performance of GDL are analyzed. This review also summarizes the current research progress of GDL including the modeling studies. Finally, various factors affecting the performance of GDL are summarized, and the development of PEMFC is prospected. It is pointed out that novel metal foam materials could replace the traditional carbon materials to construct the GDL-BP integrated structure with shorter transmission path and smaller mass transfer resistance. It is also proposed to use the emerging 3D printing technology to construct GDL with high precision and complex structure. This review has certain guiding significance for future work in optimizing the gas diffusion layer structure and improving the fuel cell performance.

Key words: fuel cells, gas-liquid flow, optional design, mass transfer, numerical simulation

摘要：

气体扩散层（GDL）在质子交换膜燃料电池（PEMFC）中起到支撑催化层、传输反应气体和排出反应过程中产生的水的作用，设计和优化GDL的结构对提升燃料电池的性能有重要作用。本文首先介绍了氢燃料电池应用前景，简述了PEMFC的结构和工作原理，指出了目前GDL的气液传输能力不足的问题，分析了孔结构、碳材料、微孔层微观结构、润湿性和耐久性五个因素对GDL性能的影响，并归纳了当前的研究进展，同时还涵盖了与GDL内传质过程相关的建模方法。最后总结了影响GDL性能的各种因素，并对质子交换膜燃料电池内的GDL发展进行了展望，指出用新型金属泡沫材料代替传统碳材料构建气体扩散层-双极板集成结构从而缩短传质路径并降低传质阻力，提出利用新兴的3D打印技术去构建高精度具有复杂结构的气体扩散层。本综述对未来优化GDL结构、提高燃料电池性能具有一定的指导意义。

关键词: 燃料电池, 气液两相流, 优化设计, 传质, 数值模拟