There are sectors of the economy that dearly need 
  electrical storage and are willing to pay for it, 
  primarily electric vehicles and renewable energy.

This has been true for 200 years. Electrical vehicles were commercially available in the 1850s, but eventually lost out to gasoline vehicles because of... power storage.

If you have actual evidence to support your argument, provide it, but "we need one" certainly isn't it. We've always needed better batteries.