Overview of hydrogen-resistant alloys for high-pressure hydrogen environment:on the hydrogen energy structural materials

With the progressive expansion of hydrogen fuel demand,hydrogen pipelines,hydrogen storage cylinders and hydrogen refuelling stations(HRSs)are the primary components of hydrogen energy systems that face high-pressure hydrogen environments.Hydrogen embrittlement(HE)is a typical phenomenon in metallic materials,particularly in the high-pressure hydrogen environment,that causes loss of ductility and potentially catastrophic failure.HE is associated with materials,the service environment and stress.The primary mechanisms for explaining the HE of materials are hydrogen-enhanced decohesion,hydrogen-induced phase transformation,hydrogen-enhanced local plasticity,adsorption-induced dislocation emission and hydrogen-enhanced strain-induced vacancy.To reduce the risk of HE for metallic structural materials used in hydrogen energy systems,it is crucial to reasonably select hydrogen-resistant materials for high-pressure hydrogen environments.This paper summarizes HE phenomena,mechanisms and current problems for the metallic structural materials of hydrogen energy systems.A research perspective is also proposed,mainly focusing on metal structural materials for hydrogen pipelines,hydrogen storage cylinders and hydrogen compressors in HRSs from an application perspective.

Development of fuelling protocols for gaseous hydrogen vehicles:a key component for efficient and safe hydrogen mobility infrastructures

Large-scale applications of fuel-cell vehicles(FCVs)are of vital importance to reduce emissions of greenhouse gases in the transportation sector,especially in the heavy-duty and long-distance scenarios.Efficient fuelling for the on-board gaseous hydrogen cylinders of an FCV is essential to achieve a fuelling experience that is comparable to that of traditional fossil-fuel-powered vehicles.However,the heating effect during refuelling leads to potential safety issues when the hydrogen temperature in the cylinder exceeds 85℃.Therefore,fuelling protocols are critical to ensure the efficiency and safety of the hydrogen mobility infrastructure.In this paper,the fuelling protocols for FCV vans and buses with type III cylinders were developed and the pre-cooling temperatures were optimized to minimize the energy consumption.Their performance was demonstrated with a 35-MPa hydrogen fuelling station.We found that FCV vans and buses can be safely refuelled in 3 or 5 minutes at a minimum,respectively,demonstrating a fuelling experience that is similar to that of traditional vehicles.

Energy Security Planning for Hydrogen Fuel Cell Vehicles in Large-Scale Events:A Case Study of Beijing 2022 Winter Olympics

Energy security planning is fundamental to safeguarding the traffic operation in large-scale events.To guarantee the promo-tion of green,zero-carbon,and environmental-friendly hydrogen fuel cell vehicles(HFCVs)in large-scale events,a five-stage planning method is proposed considering the demand and supply potential of hydrogen energy.Specifically,to meet the requirements of the large-scale events’demand,a new calculation approach is proposed to calculate the hydrogen amount and the distribution of hydrogen stations.In addition,energy supply is guaranteed from four aspects,namely hydrogen produc-tion,hydrogen storage,hydrogen delivery,and hydrogen refueling.The emergency plan is established based on the overall support plan,which can realize multi-dimensional energy security.Furthermore,the planning method is demonstrative as it powers the Beijing 2022 Winter Olympics as the first“green”Olympic,providing both theoretical and practical evidence for the energy security planning of large-scale events.This study provides suggestions about ensuring the energy demand after the race,broadening the application scenarios,and accelerating the application of HFCVs.