There is both a load and generator resource for a battery and is some markets it will register as such. So no it’s not creating net new but will often but bucketed in a generator category for the purposes of looking at mix.
So when people talk about the “generation mix,” batteries get bucketed alongside gas, wind, solar, etc. Not because they magically create energy, but because from the grid operator’s perspective they look like a dispatchable generator when discharging.
It’s one of those cases where common-sense semantics (“it’s storage”) diverge from industry practice (“it’s modeled as generation”).
Please let me know what’s confusing.
And frankly I can't find evidence for the claim that the energy sector uses the term generation for inputs to the grid in general, as opposed to just the things literally generating electricity. Which does not surprise me.