There are many different battery technologies being pursued. Some use uncommon materials, but others are just using elements available in essentially unlimited amounts. There are also means of storing energy in other forms. For example, storage of electrical energy as heat energy in sand could have a round trip efficiency of 54% at a quite reasonable cost.

https://arpa-e.energy.gov/sites/default/files/2021-03/07%20D... (now being commercialized by Babcock & Wilcox.)

The big question of storage is not if it's possible, but which of the many options will come out on top.