Source? Looking at this report[1], battery storage methods are 2x-3x the cost of "combustion turbine" (natural gas?). Presumably the kW and kWh costs for storage costs don't factor in the underlying of the energy they're storing, so the actual cost is likely higher.
If you want hours of battery storage sure, not if you want seasonal storage. That makes solar+battery a niche, not something you base your energy economy on. Besides, even if you did there's not enough minerals being mined to do battery grid storage at scale to move entire economies over to it.
I'd be very happy with renewables+batteries, but the fact it's so quiet suggests to me this isn't so simple. Certainly in Northern Europe where dark, windless winters exist - i.e. you need storage potentially for weeks, not a small few hours.
Compared to current gas prices or nuclear, batteries are dirt cheap and some of the others are almost as cheap as batteries.