Abstract: Proton exchange membrane fuel cell generates electricity, water and heat through electrochemical reaction of hydrogen and oxygen. When the water content of proton exchange membrane, cathode and anode is appropriate and evenly distributed, the fuel cell has high power generation performance. However, if water accumulates at the cathode and cannot be discharged in time, it will cause "water flooding". It will lead to the performance degradation and even shutdown of the stack. This paper deduces the law of water content in the cathode according to the water transmission mechanism inside the fuel cell, and finds out the factors that affect the water content in the stack, so as to obtain the optimization scheme to solve the "water flooding" problem. The feasibility and effectiveness of the optimization scheme are verified through the test and actual measurement, and finally the "water flooding" problem of the fuel cell cathode is solved.

Key words: Proton exchange membrane fuel cells; Flooding problem; Water transport; Air flow; Air humidity

摘要： 质子交换膜燃料电池通过氢气和空气中的氧气发生电化学反应产生电能，同时生成水 和热。当质子交换膜、阴极和阳极的水含量适当、且分布均匀时，燃料电池才具有高发电性 能。但如果水在阴极不断积聚而未能及时排出时，则会在阴极产生“水淹”现象，导致电堆 性能下降甚至停机。文章依据燃料电池内部水分传输机理，推演出阴极的水含量规律，又通 过对规律的分析找到电堆内影响水含量的因素，从而得出解决“水淹”问题的优化方案，并 通过试验实测验证了优化方案的可行性和有效性，最终解决了燃料电池阴极“水淹”的问题。

关键词: 质子交换膜燃料电池；水淹问题；水分传输；空气流量；空气湿度