June 1, 2011 - The batteries can quickly store energy brought in from solar power and wind power projects and release that electricity during peak load times. The batteries work by using a conductive solution that has free-floating ions by an electrode in an electrochemical cell. That causes a chemical reaction, inducing a current that can transfer electricity across a power grid. If the process is reversed, the battery stores electricity.

Primus Power is one of several companies funded by the U.S. government’s Advanced Research Projects Agency — Energy (ARPA-E). It’s a part of the U.S. Department of Energy that provides funding for companies that are working on green technology projects that don’t have the same market appeal of more mainstream projects — such as solar power and electric cars. The ARPA-E said it would inject $130 million into green technology companies this year.

Existing investors Kleiner Perkins Caufield & Byers and Chrysalix Energy Venture Capital also participated in the most recent funding round. The company received funding from ARPA-E as part of the agency’s GRIDS project last year, which was created to fund technology capable of improving large-scale power grid energy storage. The U.S. Department of Energy also awarded Primus Power a $14 million grant as part of a $47 million wind energy storage project in California in 2009.