Innovation: A Sodium-Ion Battery
A safe, reliable, and affordable way to store energy using sodium rather than lithium, by Aquion Energy.
Teru Onishi
Power grab
To make the most of solar and wind power, utilities need an affordable way to store energy for later use. Aquion Energy of Pittsburgh says it has developed a low-cost, longer-lasting alternative to existing storage options, including lithium-ion batteries. Aquion's battery stores electricity using sodium, which is safer and more abundant than lithium. As a result, storage costs about $300 per kilowatt-hour, roughly one-third the price of storage with lithium-ion batteries. The battery can also last up to five times as long as lithium batteries, because its electrodes are made from thicker wafers. Aquion, which recently received a $5 million grant from the U.S. Department of Energy, hopes to begin selling the batteries to solar-power companies by summer 2012 and eventually supply them to other utilities.
Stacking the deck
The electrode wafers shown here, made from manganese oxide, measure 2 inches square and 1.2 millimeters thick. They can be stacked and immersed in a solution of sodium and water to store electricity.
Recharge and reuse
Aquion's sodium-ion battery, which is about the size of a breadbox and weighs 5 pounds, is nontoxic and 100 percent recyclable.
"Energy storage has never been this safe, reliable, and affordable." —Scott Pearson, CEO, Aquion Energy
