Startup Aims to Bring the Liquid Battery to Market
A Cambridge company is developing cheap batteries that can store power from wind turbines and solar panels.
The workspace at Liquid Metal Battery’s small basement headquarters in Cambridge, Massachusetts, looks more like a machine shop than a high-tech lab you might expect from a spin-off from MIT.
In the place of vacuum chambers and rows of sealed glove boxes sit a large bandsaw, a drill press, and a simple welding station. In another corner sits an ordinary kiln like you might find in a pottery studio. Although the company’s technology is based on advanced chemistry, the batteries look rudimentary: thick-walled steel cans that the researchers fill with powder scooped from large buckets and barrels.
The simplicity is by design. The company’s goal is to make batteries so inexpensive that they can cheaply store wind power generated at night when it is often windy but power demand is low, for use during times of peak demand during the day. It has attracted millions of dollars in early-stage investments from Bill Gates, the French oil company Total, and the U.S. Advanced Research Projects Agency for Energy.
Liquid Metal, which was founded in 2010 but only started operating in earnest last fall when it expanded from seven to 17 employees, is one of several new companies hoping to learn from the challenges faced by an earlier wave of clean-energy startups. Clean-energy companies have struggled in part because incumbent technologies—such as fossil-fuel power plants, gas-powered cars, and even conventional solar cells—are so cheap, and because utilities favor established technologies.
Some earlier battery startups focused on, say, a promising electrode material discovered in a lab, only to discover that manufacturing the material erased much of the cost savings that the material promised. The new group of startups, which includes a spin-off from A123 Systems called 24 M and another called Aquion, are taking a close look at manufacturing costs from the beginning. Liquid Metal has also identified markets that can allow it to initially afford high costs until large-scale production makes its batteries more affordable.
Liquid Metal Battery is so named because the powders its researchers pour into its battery cells are heated to the melting point, when they naturally segregate themselves into three layers, the positive and negative electrodes, and the electrolyte that separates them. These now-liquid materials are highly conductive, so the batteries can be discharged and charged quickly, accepting charge one millisecond and returning it the next, if necessary, to help stabilize fluctuations of supply and demand on the power grid.
The idea originated with Donald Sadoway, a chemistry professor at MIT, and Gerbrand Ceder, a professor of materials science at MIT, who wondered if it might be possible to essentially reverse processes like those used to make aluminum. For example, electricity is used to produce aluminum from aluminum oxide—if that chemical reaction could run the other way, it would produce electricity, and the system would function as a battery. Sadoway’s graduate student, David Bradwell, found a way to get the electricity that’s put into the process back out again.
The company believes the design can be built in existing factories with contract manufacturing, and since there’s no need to build its own factories at first, its capital costs would be greatly reduced. Still, until the technology reaches mass production, its costs will be relatively high. This is where a bit of market savvy is important. The founder’s decision to build batteries that are not only capable of storing large amounts of energy at low-cost, but can also respond in milliseconds, will give it access to markets where it can charge high prices for storing and delivering power to the grid to make up for fluctuations in supply and demand—something that’s becoming important as more wind and solar power, which are intermittent, is installed.
As the production scale increases and costs come down, Liquid Metal plans to serve larger-scale markets, such as buying cheap electricity at night and selling it in the middle of the day, when prices are higher. Because the technology is flexible the company can decide how to use its battery capacity, always picking the most lucrative market.
Liquid Metal plans to take advantage of two opportunities created by the government. The first is actually a product of deregulation: the government set up framework for establishing open markets for power. This allows the company to register as an independent power provider without going through a utility or getting regulators to allow utilities to charge for the service. This gives even a small company a clear path to earning money. The company could also benefit from a ruling by the Federal Energy Regulatory Commission that technologies with fast response times can be paid more for their services. This could give such technologies an edge over existing power plants, which can take several minutes to respond.
Liquid Metal Battery still faces challenges, such as confirming that its cells are durable enough to make the economics work out. Even with relatively low capital costs, it may need to call on partners, such as Total, for help not only with funding, but also for experience in large-scale operations. Liquid Metal plans to announce new funding—this time from venture capitalists—in the coming weeks.