A review on the development status and future trend of liquid hydrogen technology

As a kind of clean secondary energy, hydrogen has a broad development prospect in the energy field. In the whole industrial chain of hydrogen production, storage, transportation and application, the storage and transportation of hydrogen is a challenging key link, especially in long-distance transportation and large-scale storage. Liquid hydrogen, as a competitive technology, can improve the economy and security of hydrogen storage and transportation. The commercialization of liquid hydrogen urgently needs to improve the technology of hydrogen liquefaction to reduce the cost of producing liquid hydrogen. Through the comparison and thermodynamic analysis of the hydrogen liquefaction processes, the energy consumption of each link and its weight order are obtained, and the effective technical way to reduce energy consumption is found. The improvement of hydrogen liquefaction efficiency needs to be comprehensively carried out from the aspects of output scale, improvement of system process flow including precooling technology, and improvement of key core equipment efficiency. The theoretical minimum energy consumption of hydrogen liquefaction is about 3.3 kWh/kg, which is equivalent to 8% of the stored energy of hydrogen. In the future, the energy consumption expected target of hydrogen liquefaction is about 6 kWh/kg. Evaporation loss of liquid hydrogen during storage and transportation is also a challenging problem to be solved urgently. The development trend of technology in the future is put forward, including the use of mixed refrigerant precooling technology and new centrifugal compressor technology, high-speed motor-driven magnetic levitation technology, etc. This improvement direction will promote the commercialization of liquid hydrogen in hydrogen energy field.