In the proton exchange membrane fuel cell (PEMFC) for vehicles, the changes in gas composition and oxygen accumulation may exist during the parking process even by using a shut-down strategy of oxygen consumption, which can lead to the hydrogen/air interface. However, this process of oxygen accumulation is often ignored. Thus, in this work, the diffusion rate of the gas, the gas composition changes, and the starting voltage of the PEMFC stack are discussed. According to the experiment, it is proved that the poor gas tightness of the stack results in the formation of the oxygen inside the stack during the parking process and the threshold parking time of no hydrogen inside the stack is above 1 h. Then, a parking control strategy is proposed by injecting hydrogen into the anode, and the hydrogen injection cycle is set as 1 h by the anodic hydrogen concentration. Based on the strategy, the starting voltage of the fuel cell is declined from 18 V to 3 V. That means the hydrogen/air interface is declined. Therefore, the durability of the PEMFC for vehicles can be enhanced.

中文翻译：

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汽车质子交换膜燃料电池停车控制策略研究

在用于车辆的质子交换膜燃料电池（PEMFC）中，即使使用氧气消耗的关闭策略，停车过程中也可能存在气体成分和氧气积累的变化，这可能导致氢气/空气界面。然而，这种氧气积累的过程往往被忽视。因此，在这项工作中，讨论了气体的扩散速率、气体成分的变化以及 PEMFC 堆的启动电压。经实验证明，由于电堆气密性差导致在停放过程中电堆内部形成氧气，电堆内无氢气的阈值停放时间在1h以上。然后，提出了通过向阳极注入氢气的停车控制策略，并且根据阳极氢气浓度设定氢气注入周期为1h。基于该策略，燃料电池的启动电压从18 V下降到3 V。这意味着氢/空气界面下降。因此，可以提高车辆用 PEMFC 的耐久性。