The main problem for energy storage investment is that investors demand a complex, patentable system, but the best systems are too simple for that. So, there will be a rash of over-complicated storage scheme startups, and not enough simple ones.

So to field a good system, you need to rely on grants, instead. A grant might suffice to prove viability, but it takes investment to build a factory to build systems in the huge volume we will need. So, the parts for your system need to be already manufactured in volume for some other purpose. And you probably need a utility to commit to a huge order and pay in advance.

We need an investment fund that selectively funds scaling up the simple storage systems venture capital can't.