That first reference is talking about Lithium Iron Phosphate...

That first reference is talking about Lithium Iron Phosphate (LFP), they have been around for ages and are currently fitted to nearly all the Chinese EVs and the standard range Tesla 3 & Y. They have a lower energy density than the other Lithium chemistries but have a higher charge tolerance and are slightly cheaper per kWh of storage. LFP batteries don't use Nickle, Cobalt or Manganese. CATL, BYD and many of the planed new western battery factories are predominately LFP.

Talk of an Iron-Air battery has been around for a while as well, no one has actually demonstrated a working battery yet so ATM its just more hot air. The big news with Form Energy is they have publicly set a cost target of $20 kWh. If they can get anywhere near that with a reasonable working life and round trip efficiency then they will have the battery storage market all to themselves because no one else will be able to compete with that but talk is cheap and they have to actually produce one first.

VFRB, the other flow batteries and the various Lithium chemistries have the runs on the ground after many years of development. Even if a totally new economically viable battery is invented it will take years to ramp up production sufficiently to compete with the current crowd.