Aquion Energy raises $20M for its grid battery

Earlier this year Aquion Energy, which is developing a battery for the power grid, told us that the company was looking to raise money by the summer for a 500 megawatt-hour factory. Well, here’s proof of that: According to a filing, the startup has closed $20 million of a planned $30 million round and has brought on investor Foundation Capital in addition to existing investor Kleiner Perkins Caufield & Byers.

Four-year-old Aquion has developed a modular battery that uses basic, widely-available (and edible) materials, like sodium and water. The company says its bulk battery will be low cost compared to the current batteries that are being piloted on the power grid, and could be as cheap as one-tenth the cost of the alternatives. The Electric Power Research Institute (EPRI) says that grid-scale lead acid batteries cost around $950-$1,590 per kilowatt, or $2,770-$3,800 per kilowatt-hour, and lithium-ion batteries cost about $1,085-$1,550 per kilowatt, or $4,340-$6,200 per kilowatt-hour.

Aquion’s goal is to use its grid battery to help utilities integrate more solar and wind power. Solar and wind are variable power sources (when the sun doesn’t shine and the wind doesn’t blow they don’t produce power) and energy storage will be a crucial way to even out those ups and downs for the grid. Aquion also says its battery, which it thinks can last 20-30 years, can withstand a wide range of temperatures without losing storage capacity, meaning installing it onsite at a solar farm wouldn’t affect the battery’s performance.

Founder and chief technology officer Jay Whitacre developed the basic science for Aquion at Carnegie Mellon University. The battery pairs a carbon anode with a sodium-based cathode. Water-based electrolytes shuttle ions between the two electrodes during charging and discharging. Traditional batteries often use solvent-based electrolytes.

The idea was to create a battery out of the most basic elements that could produced at a massive scale for cheap. Aquion Energy business development chief Ted Wiley, described the battery to us as “literally edible—every single material in the battery.”

The company is now looking to transition from “an early-stage technology development organization into a full-fledged product company,” as Kleiner chairman Ray Lane described it earlier this year. Commercializing the tech will be tough. For example, just selling into a utility-scale energy project can take as long as three years, and the factory will cost an estimated $75 million to $80 million.

Image courtesy of Suicine, and Aquion Energy