There are technologies for battery storage that don't look like batteries. Thermal energy storage is an example. It consists of heating something very big that holds a lot of heat and releases it slowly, then using that stored heat to generate electricity while it cools down. This isn't suitable for home use, but at the city scale, or larger, it's quite efficient:

https://en.wikipedia.org/wiki/Thermal_energy_storage

> There are technologies for battery storage that don't look like batteries. Thermal energy storage is an example.

Yeah, there's also pumped water storage, and other forms of gravity/kinetic storage, various means of chemical energy storage, and all kinda other neat battery-like ideas folks have been trying/using.