"There are liars, damn liars, and battery guys. Although fuel cells and flow batteries are a different class altogether." That quote is variously attributed to Thomas Edison, venture capitalists, and assorted technologists.

According to sources close to the deal, flow battery aspirant EnerVault has been unable to land additional investment and is restructuring the firm as it looks for new owners. EnerVault has confirmed that it is "seeking new owners" and going through "a company restructure."

The company will be issuing a formal release later today.

Jim Pape, a former SunPower exec and recent CEO at EnerVault, left the startup at the end of last year. Julie Blunden, once with SunPower and now with SunEdison, was an advisor to the company. Former CEO and current CSO Craig Horne has been making aspirational claims about the company for six years. 

I keep hearing that the energystoragemarket is now like the solar market was six to eight years ago. I would agree -- in that we are due in for a wave of promises on new technologies that never materialize as dozens of companies fail in a venture capital/public relations/energy analyst hangover.

So, yes -- I believe storage will be like the solar industry in that respect.

Founded in 2008, EnerVault had gained more than $24.5 million in funding from investors including 3M, Total, Mitsui Global Investment, Oceanshore Ventures, and TEL Venture Capital.

As GTM's Stephen Lacey reported last year, the company claims: 

  • The capital cost of its first commercial project, a 1-megawatt-hour system, will get close to beating DOE's cost targets (PDF) for commercial-scale redox flow batteries.
  • A project in Turlock, California will provide 250 kilowatts of power for four hours to Pacific Gas & Electric. (It was supported by the DOE's storage demonstration program under the stimulus package, which provided $4.7 million in assistance. The flow battery will be co-located with a PV system and a water pump -- if new owners can be found.)

A storage tank is installed at EnerVault's first commercial site in Turlock, California. Image credit: EnerVault

As Lacey reported, flow batteries convert chemical energy into electricity by pumping electrolytes through a stack of electrochemical cells. EnerVault's flow battery technology uses iron-chromium electrolytes. The company said the chemistry is safer and less acidic than vanadium and less expensive than other chemistries being developed.

While deployment to date has been limited, flow batteries do offer longer, more consistent energy delivery -- a reason why startups and investors are still attracted to the technology.