It's hard to store. It leaks away. It has poor energy density by volume (and much of the energy simply goes to compress the damn stuff) - only 3x li-ion, for your trouble. It has a crappy round-trip efficiency - only 50% for water -> electrolysis -> fuel cell. It's just a shitty battery.
The only thing it's got going for it is that it's a way of greenwashing fossil fuels.
It's hard to store. It leaks away. It has poor energy density by volume (and much of the energy simply goes to compress the damn stuff) - only 3x li-ion, for your trouble. It has a crappy round-trip efficiency - only 50% for water -> electrolysis -> fuel cell. It's just a shitty battery.
The only thing it's got going for it is that it's a way of greenwashing fossil fuels.