Toyota has unveiled a concept for an innovative system to improve the efficiency of vehicles running on liquid hydrogen. The system allows the evaporated hydrogen to be reused thanks to a self-charging pump, while significantly reducing fuel loss.
Image source: Toyota
The Japanese automaker continues to actively develop hydrogen technology. In 2023, Toyota unveiled the GR Corolla H2 concept with a liquid hydrogen storage system at -253 degrees Celsius. However, despite the use of ultra-low temperatures to prevent the liquid from boiling, some of the hydrogen still evaporates, increasing fuel loss.
To address the issue, Toyota introduced new self-supercharger fuel pump technology at the 2024 Super Taikyu Series. This system uses the pressure of evaporating hydrogen to compress it by 2-4 times, turning it into a fuel that can be reused without additional energy costs. But that’s not all. In the future, it is planned to use the remaining evaporated hydrogen to power a fuel cell, which will power the hydrogen pump, further increasing the efficiency of the system.
Image source: Toyota
It is worth noting that working with liquid hydrogen involves a number of technical difficulties associated with both storage and the configuration of the entire system. Washington State University professor Dr. Jacob Leachman emphasizes that hydrogen pumps are the most vulnerable components in all hydrogen systems, both cryogenic and gaseous, and he believes that Toyota has made a breakthrough by developing a pump that uses a cryogenic plant for compression hydrogen. “This is progress that is needed for anyone developing liquid hydrogen vehicles,” Leachman said.
At the same time, the professor notes that one of the main problems remains sealing containers with liquid hydrogen. If hydrogen boils inside a closed container, the pressure can rise to 140 megapascals (MPa), creating additional challenges for developers of such systems.