Just use that electricity to make hydrogen in the first place, hydrolysis is approximately as efficient as aluminum smelting already (and both are over 90%)...
The point is that it is beneficial to store the energy as Aluminium instead of hydrogen gas.
See https://www.sciencedirect.com/science/article/pii/S258929911... as an example overview.
Aluminium takes a big juicy bunch of electricity. Its very energy intensive. But, if we can extract a good portion of that aluminium energy as hydrogen gas, then aluminium acts as a highly energy dense battery.
It can then be effectively used for grid scale energy storage.
I expect a reasonable high density low pressure hydrogen storage solution to happen sooner at any scale, a solid fuel isn't particularly practical either except in a one-use battery.
Recycling generally avoids smelting aluminum because Aluminum in say cans only has an atomic scale coating of Aluminum oxide around pure Aluminium.