The problem with batteries is that they are costly to produce if we’re talking about ones that reverse chemical reactions. This is why I rolled my eyes at Elon suggesting we connect batteries to all our renewables. (The cost I learned from Factorio). Other types of batteries, like potential energy buffers are more practical, but also extremely location specific. There is a Technology Connections video about it. Also for example, some rollercoasters have flywheels to slowly build up rotational inertia and then release it all at once. So if we were to store the excess energy, it would probably be done so this way, but baseline power obviously just seems more practical

Link https://uwaterloo.ca/waterloo-institute-sustainable-energy/sites/default/files/uploads/documents/magdy_salama_research_spotlight_poster_120716.pdf