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The basic prerequisites for a well-functioning fuel cell stack are identical MEAs with similar performances and power outputs. One poor MEA in a cell stack can negatively affect the overall performance as well as the lifetime of this fuel cell stack. During this work, HT-PEM-MEAs of four different providers were tested using the accelerated stress test load cycling at high current densities (14 min at 1.0 A/cm² and 6 min at 0.6 A/cm²) and compared with each other. In addition, internal-batch comparisons for two of the four suppliers were carried out. There are distinctive differences between suppliers as well as within a batch, clearly showing the need for the development of uniform quality assurance measures. In-situ electrochemical as well as ex-situ micro-computed tomography results will be presented for this MEA evaluation.

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In order to control the batch quality of membrane electrode assemblies (MEA), two new short tests have been developed. The first being a rapid test, composed of a start‐up and break‐in followed by initial characterization and has a test duration of about 65 h, while the second is a flash test, which is reduced by the break‐in, so that the maximum duration is 8 h. These tests have been compared with classical accelerated stress tests like load cycling at high current densities and start/stop‐cycling. For the investigations presented in this publication, high temperature polymer electrolyte MEAs from two different suppliers were used. The extensive electrochemical characterization clearly shows that the newly introduced fast tests can be used to check the batch qualities. In addition to the electrochemical investigations, the phosphoric acid content of all MEAs has been determined and ex situ micro‐computed tomography analysis has been performed.