ASN General Discussion, page-198

I think we will see a split. I've said It before, but: Firstly, large scale lithium battery storage is becoming more expensive as all the minerals needed climb in price from automotive demand, and are better suited to automotive, tools and small equipment. Secondly, large scale Lithium is a large scale fire fighting problem.
Bromine flow and non-flow batteries of differing chemistry are better suited to the grid or home storage. While not being a fire risk, can safely live under your home while you sleep.
As countries rely more on renewable energy, the demand for rainy day storage will expand.