Safety Demands for Automotive Hydrogen Storage Systems

Fuel storage systems for vehicles require a fail-safe design strategy. In case of system failures or accidents, the control electronics have to switch the system into a safe operation mode. Failure Mode and Effect Analysis (FMEA) or Failure Tree Analysis (FTA) are performed already in the early design phase in order to minimize the risk of design failures in the fuel storage system. Currently, the specifications of requirements for pressurized and liquid hydrogen fuel tanks are based on draft UN-ECE Regulations developed by the European Integrated Hydrogen Project (EIHP). Used materials and accessories shall be compatible with hydrogen. A selection of metallic and non-metallic materials will be presented. Complex components have to be optimised by FEM simulations in order to determine weak spots in the design, which will be overstressed in case of pressure, thermal expansion or dynamic vibrations. According to automotive standards, the performance of liquid hydrogen fuel tank systems has to be verified in various destructive and non-destructive tests.