Abstract High oxygen transport resistance in the cathode is a main cause of the low performance of high temperature proton exchange membrane fuel cell (HT-PEMFC), and therefore to determine the contribution of different mass transport processes to the oxygen transport resistance is beneficial to the subsequent research work. In this paper, the molecular diffusion resistance ( R M ) in the cathode was successfully calculated by measuring the limiting currents with using different diluent gases. And the oxygen transport resistance in phosphoric acid ( R P A ) was analyzed by changing the humidity and temperature. It was found that the total oxygen transport resistance ( R t o t a l ) increased obviously with the increase of the humidify, and the variation of R t o t a l under different conditions was mainly related to the change of R P A . Combined with the phenomenon that the experimental value of R M was less than the calculated value at high humidity, but higher than that at high operation temperature, we speculate that the cause of that R P A increased obviously at high humidity is the occupancy or blockage of gas phase transport channel in catalyst layer (CL) by phosphoric acid due to the water absorption of phosphoric acid in CL and the swelling of membrane. This consequence indicates that it is the change of phosphoric acid distribution that dominate C i s the R t o t a l at high humidity.

中文翻译：

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高温质子交换膜燃料电池阴极传质阻力的测量与分离

摘要 阴极氧传输阻力高是高温质子交换膜燃料电池（HT-PEMFC）性能低下的主要原因，因此确定不同传质过程对氧传输阻力的贡献有利于提高质子交换膜燃料电池的性能。后续研究工作。在本文中，通过使用不同稀释气体测量极限电流，成功计算了阴极中的分子扩散电阻（ RM ）。并通过改变湿度和温度来分析磷酸（RPA）中的氧传输阻力。发现总氧传输阻力(R total )随着湿度的增加而明显增加，不同条件下R total 的变化主要与RPA的变化有关。结合高湿时RM的实验值小于计算值而高于高操作温度的现象，我们推测高湿时RPA明显升高的原因是气相的占用或堵塞。由于 CL 中磷酸的吸水和膜的溶胀，磷酸在催化剂层 (CL) 中传输通道。这个结果表明，在高湿度下，支配 C 的是磷酸分布的变化是 R 总和。我们推测，高湿度下RPA明显增加的原因是由于CL中磷酸吸水和膜膨胀，磷酸占据或堵塞了催化剂层（CL）中的气相传输通道。这个结果表明，在高湿度下，支配 C 的是磷酸分布的变化是 R 总和。我们推测，高湿度下RPA明显增加的原因是由于CL中磷酸吸水和膜膨胀，磷酸占据或堵塞了催化剂层（CL）中的气相传输通道。这个结果表明，在高湿度下，支配 C 的是磷酸分布的变化是 R 总和。