> They worked out how to store 1H as a solid

MgH2, Magnesium Hydride was the last solid hydrogen storage medium that I saw they were working on. The problem is that it is solid, which makes it a terrible refueling storage medium, you need a liquid(like gasoline) or a gas that can be safely condensed(like propane), solids are difficult to extract the energy back out from, though not impossible, especially if they sublime under heat or are able to be activated while in a solution.

Palladium is also a fantastic Hydrogen storage device, with being able to store up to 900x its volume in hydrogen or something like that, palladium is already expensive for its unique properties and uses in catalytic converters.