# Fluidic shows a peek of its metal air batteries for off and on the grid

A quiet startup in Scottsdale, Arizona called Fluidic Energy showed off its grid-scale metal air batteries for one of the first times in a video at the ARPA-E Summit this week (embedded below). The battery technology was developed at Arizona State University by ASU Materials Science Professor and Fluidic founder Cody Friesen, and spun out several years ago.

The video shows Fluidic’s batteries installed under what looks like a radio or cell phone tower, and Friesen said that the company’s batteries are already being tested in the field in developing markets where the grid is unreliable as a replacement for diesel generators or lead acid batteries. Friesen said that using the “tens of millions of cell hours in the field,” the company plans to target the grid market in the U.S.

[vimeo http://www.vimeo.com/60446135 w=500&h=281]

A battery is usually made up of an anode on one side and a cathode on the other, with an electrolyte in between. Fluidic’s battery uses zinc as the metal for the anode, air as the cathode, which is drawn in from the environment, and a liquid electrolyte. Air batteries have long been attractive to researchers because oxygen is abundant, free, and doesn’t require a heavy casing to keep it inside a battery cell.

Reporter Tyler Hamilton wrote some details about Fluidic’s technology in an article back in 2009. Hamilton wrote that one of the key innovations is that Fluidic’s battery uses an ionic liquid (liquid salt) for its electrolyte, instead of an aqueous solution that is made up of water. Water-based electrolytes can evaporate and tend to decompose when the voltage gets too high in metal air batteries.

Fluidic’s other innovation, reported Hamilton, is a metal electrode architecture that uses different sized pores to combat a problem with batteries where sharp needles called dendrites are formed. These needles occur because the metal isn’t plating across the battery uniformly and can ruin the battery.

The combo of these innovations are supposed to deliver a metal air battery that can be recharged, has high energy density (amount of energy that can be stored), and is inexpensive. If the battery was used in an electric car, it could have 400 to 500 mile range for the price of a lead acid battery. The ARPA-E site says the battery is shooting for 5,000 charge and discharge cycles. Friesen says in the video that the battery is the first proven, high-cycle rechargeable metal air battery out there.

Fluidic has a $5.13 million grant from the Department of Energy, and a$3 million grant from ARPA-E. A couple weeks ago Fluidic closed on a round of $13.8 million, in 2011 raised$33.4 million and in 2009 raised \$1 million. This article in Phoenix Business Journal says inverter manufacturer Satcon and Chevron Energy Solutions are investors.

At one point in 2011 former First Solar President Bruce Sohn had joined Fluidic as CEO, but he only stayed on for about 8 months. Former WalMart CEO Lee Scott was sitting on the company board as of last year, and raved about Fluidic at the ARPA-E Summit in 2012.

Other companies developing metal air batteries include IBM, working with Japanese chemical companies Asahi Kasei and Central Glass, Eos Energy Storage, and PolyPlus. Metal air batteries have been under development for decades, and some think the technology is overhyped.