Discarded EV batteries with 70% life remaining seem like a viable path to energy storage for households.
Maybe someone's gathering up identical packs, eg a specific generations of Tesla Model 3 packs, and turning just those into power walls or grid storage.
That said, methinks since battery recycling tech has scaled up ahead of demand, it's cheaper and faster to extract the misc minerals and make new, much much better, batteries (for grid storage).
I'm noob, so really wouldn't know. I guess we'll see.