The performance and life proton exchange membrane fuel cell (PEMFC) depend on local distribution of internal temperature, voltage, current and humidity, while its overall performance and life of PEMFC stack are directly affected different external operating conditions. However, the nonuniform distribution of temperature, voltage, current and humidity can occur anywhere in a PEMFC stack. In order to solve this problem, this study developed a real-time microscopic diagnosis technology for PEMFC stack performance. It applied the micro-electro-mechanical systems (MEMS) technology to build, a flexible 4-in-1 (temperature, voltage, current and humidity) microsensor, which can measure the four main physical properties inside the PEMFC stack, so as to determine the optimum operating conditions. The flexible 4-in-1 microsensor developed in this study was successfully applied to the interior of a motorcycle fuel cell range extender, and detected that the physical properties in different parts of the PEMFC stack, especially on temperature. The measured data could be used to determine whether a thermal stress concentration has been generated inside the PEMFC stack, thus, the operating conditions could be changed accordingly to relieve the concentration. Moreover, the data of local voltage and current could also indicate the local reaction status and the relationship between the reaction rate and temperature and humidity. The proposed technology can help manufacturers to use the collected data to adjust the production parameters, thereby accelerating fuel cell development, and extending cell performance and life.

质子交换膜燃料电池（PEMFC）的性能和寿命取决于内部温度，电压，电流和湿度的局部分布，而PEMFC电池组的整体性能和寿命直接影响不同的外部运行条件。然而，温度，电压，电流和湿度的不均匀分布可能发生在PEMFC堆栈中的任何位置。为了解决这个问题，本研究开发了一种用于PEMFC电池组性能的实时显微诊断技术。它采用微机电系统（MEMS）技术构建了一种灵活的四合一（温度，电压，电流和湿度）微传感器，该传感器可以测量PEMFC电池组内部的四个主要物理特性，从而确定最佳工作条件。这项研究中开发的灵活的四合一微传感器已成功应用于摩托车燃料电池增程器的内部，并检测到PEMFC电池组不同部分的物理特性，尤其是温度。测得的数据可用于确定PEMFC堆内部是否已产生热应力集中，因此可以相应地更改操作条件以减轻集中。此外，局部电压和电流的数据还可以指示局部反应状态以及反应速率与温度和湿度之间的关系。提出的技术可以帮助制造商使用收集的数据来调整生产参数，从而加速燃料电池的开发，并延长电池的性能和寿命。