Hydrogen can be stored underground (and is), just like natural gas. This is much cheaper per unit energy storage capacity than storing energy in batteries.
AFAIK H2 is way more difficult to contain than natural gas, as the molecules are so tiny. Very hard to build a container that doesn't continuously leak the gas.
there is a short term battery based storage but the long term storage for the winter months is the h2 storage. I think the system is very expensive but a cool prove of concept and for sure a step in the right direction.
