Box car sized energy storage systems

Will this new form of energy storage system make its’ way to mainstream America any time soon?  Will it evolve as cellular phones did where they were once the size of small breadboxes and now fit on  a wrist watch?  For now, the large-scale utility energy storage systems can take the edge off of soaring regular power energy grid costs by capturing solar energy and storing it for peak usage;  if you can get used to seeing a box car sized storage system.