A review of testing procedures for proton exchange membrane electrolyzer degradation

Durability of electrolyzers is one of the main challenges for their widespread commercialization, although many commercial PEM electrolyzer manufacturers claim durability up to 30,000 h or even longer. Nevertheless, their degradation processes are increasingly investigated. There is a need to promptly diagnose degradation causes by monitoring the resulting performance decay. However, a wide spectrum of procedures for degradation testing makes it difficult to compare the obtained results, thus makes their practical application unsuitable. In order to systemize the proposed testing procedures, an overview of investigations that include PEM electrolyzer degradation testing is presented here, together with a comparative analysis and a critical review. The reviewed papers are grouped in accordance to whether the degradation tests were performed under constant or dynamic operating conditions. In addition, the review includes the advances and perspectives in accelerated test development. It was noticed that incomplete or inadequate membrane initial conditioning or activation affects the obtained results and, thus, the extracted conclusions. Therefore, before conducting any relevant degradation test, it is necessary first to define and carry out a suitable activation procedure, in order to compare the results of different degradation tests and reach the correct conclusions, which should be the subject of further research.