Research progress on membrane electrode assembly for low-pressure electrochemical hydrogen compressors

The widespread use of hydrogen fuel cell vehicles (FCVs) is beneficial for reducing transportation's reliance on traditional fossil fuels, providing significant environmental benefits and potential for large-scale application. However, the purification and storage of hydrogen are pressing issues that need to be addressed for the widespread application of hydrogen energy. The electrochemical hydrogen compressor (EHC) can purify hydrogen while compressing it, offering numerous advantages and meeting the specific requirements of FCVs for hydrogen. Meanwhile, with the increasing necessity for industrial hydrogen purification and the promotion of hydrogen mixed in natural gas pipeline, the application of low-pressure (<5 MPa) EHC system is expected to expand significantly. This paper provides a detailed introduction to the working principles and structures of EHC, comparing their advantages and disadvantages with traditional hydrogen compressors. To address the practical challenges in the application of the low-pressure EHC system, this paper summarizes the research progress on key components such as proton exchange membranes, gas diffusion layers, and catalyst layers. Additionally, it reviews strategies for water management and the mitigation of poisoning within the membrane electrode assembly. Finally, it summarizes the challenges that the low-pressure EHC system is facing and offers prospects for future research directions.