Experimental Evaluation of High-Pressure Hydrogen Compatibility of Rubber Sealing Components on Hydrogen Storage System for Vehicles

Rubber sealing components are indispensable in on-board high-pressure hydrogen storage systems. However, they are susceptible to hydrogen-induced expansion and cracking in high-pressure environments, which can lead to seal failure and compromise system safety. This study investigates the effects of rubber type, environmental temperature and decompression rate on hydrogen compatibility of rubber sealing materials. Samples of different rubber types were exposed to prolonged high-pressure hydrogen environments at varying temperatures, including room temperature and deep-low temperatures. Following exposure, the samples underwent rapid decompression at different rates. The study observed the cracking status and measured the volume and mass change rates of the samples. Key findings indicate that all materials exhibited mass change rates well below the 10% standard, with rates consistently under 0.18%. FKM showed more pronounced volume change compared to EPDM and HNBR. When the decompression time was controlled within 10 s, increasing decompression rates slightly elevated mass change rates, but the changes remained minimal, and volume change rates were less affected. Exposure temperature significantly influenced volume change rates, with samples exposed to 15 °C showing substantial volume expansion (~30%), while those exposed sequentially to 15 °C and − 40 °C or only to 40 °C exhibited lower volume changes (<25%). In summary, while FKM demonstrates excellent mass stability, its volume expansion raises concerns. EPDM and HNBR offer more balanced performance. These insights are critical for enhancing the safety and reliability of high-pressure hydrogen storage systems.