[jmopp]

I always thought of technologies like these as potential solutions to the grid-storage problem: excess solar and wind energy can be put into electrolysis, and then the metals can be burned to provide base load power — while keeping lithium for portable use-cases

[kaliszad]

I would rather use a process that uses more abundant elements and can be used to (re)produce electricity directly without burning: https://news.ycombinator.com/item?id=37548917 Generally, it is a good idea to lower the temperature needed to produce your fuel as that usually is just waste heat. Melting iron oxides needs very high temperatures which makes everything more complex.

[NikkiA]

Still magnitudes less efficient than just building gravity batteries.