Could an M.I.T. Startup’s Liquid Metal Batteries Save the U.S. Electric Grid?
With more than 450,000 miles of high-voltage transmission cables, the U.S. electric grid is a sprawling system that represents one of the greatest engineering achievements of the 20th century. Yet, after decades of ostensible neglect, it is showing its age, worrying experts and policymakers alike.
Seeking to reverse this decline, entrepreneurs have homed in on the electric grid, leveraging cutting-edge research to fundamentally transform the nation’s power supply network and make it more efficient and reliable. Though still in its infancy, this “smart grid” modernization effort has already fueled a wave of innovation that could yield far-reaching benefits.
Connecting the electric grid to the internet could, for example, allow operators to rapidly identify and subsequently patch power disruptions. Next-generation technologies could reduce the costs associated with generating and transmitting power, and they could also help solve a vexing problem: How to effectively store the energy generated by renewable energy sources. This obstacle, it turns out, is well on its way to being overcome thanks to pioneering work being done at Ambri, a Cambridge, Massachusetts-based startup run by a group of M.I.T. graduates and professors.
How, exactly, is Ambri surmounting one of the most serious barriers to improving electric grid reliability and performance? Well, answering that question requires a trip to an M.I.T. lab run by Dr. Donald Sadoway, who co-founded the company along with David Bradwell, one of his former graduate students.
A professor of materials chemistry, Sadoway sought to develop an inexpensive battery capable of storing the energy generated by solar and wind turbine systems, Mike Kearney, a principal on the company’s corporate development team, says. Because he intended to deploy it on the electric grid, Sadoway disregarded established methods commonly used to produce lithium-ion and other kinds of conventional batteries.
“Our company is entirely based on the commercialization of the liquid metal battery technology. In fact, when we were founded, the company was called the Liquid Metal Battery Corporation,” Kearney says. “The technology itself is unlike any other battery technology that’s in development or on the market today. We’re the only battery where all three primary components of the battery are liquid.”
Unlike widely available models, Ambri’s liquid metal batteries are comprised of cells that feature three self-separating liquid layers that float on top of one another. Its liquid composition, M.I.T.’s Technology Review reported, is the secret to its improved functionality, as it’s able to withstand high temperatures—in excess of 500 degrees Celsius—while still maintaining its structural integrity. Ambri’s liquid metal batteries, Kearney says, consequently hold a few distinct advantages over standard models.
“The first is cost and that’s the result of picking inexpensive materials, creating an inexpensive design for the battery that’s very simple and elegant, and then using simple and inexpensive manufacturing processes to make the batteries at scale,” he explains. “The second benefit is lifespan. For something that you’re putting on the electric grid, you need it to last for decades. Our technology is fundamentally different than other battery technologies out there and we expect our systems to last for on the order of 20 to 30 years.”
What effect could that have on the electric grid? It has the potential, Kearney argues, to radically improve the electric grid’s functionality. Under its current model, the electric grid is structured to meet peak demand, meaning periods when electricity use surges—in the early evening during a heat wave in the middle of the summer, for instance.
“The largest challenge we have is to deliver electricity the moment that it’s demanded 365 days a year. If you’re off by just a little bit then you have blackouts,” he says. “We want to build out a system to meet average demand—one that literally requires one-half of the generation resources that we currently have. Batteries could be charged when the grid is producing more electricity than is needed, and then dispatched to meet peak demand. It’s a much more efficient, more sustainable, and more cost effective way of running a power system.”
Liquid metal batteries could further disrupt the existing paradigm, Kearney stresses, by effectively storing the electricity generated by clean energy systems. “Under the current system design, our potential to add solar and wind is significantly limited, because you can’t tell the sun when to shine and the wind when to blow,” he says. “With energy storage, you can actually conceivably get to a 100% renewable grid and still pay significantly less than you’re currently paying for electricity in some markets.”
With public and private investment in smart grid projects continuing to grow—since it was passed in 2007, the Smart Grid Investment Grant program has funneled roughly $8 billion toward research and development initiatives—Ambri has seen strong demand for its genre-bending technology. The company has five ongoing projects in New York City, Massachusetts, Hawaii, and Alaska, Kearney says, and it recently opened its first production facility in Massachusetts.
“We opened up a prototype manufacturing plant in Marlborough last year,” he says. “We are just beginning the search for a full-scale manufacturing plant, which will be here in the U.S. To us, it’s a really exciting time to be doing it here in the U.S. and it’s great that local innovation is breeding local jobs.”
Though it’s taken a little while for smart grid efforts to gain momentum, support is steadily rising. Besides improving reliability, these upgrades could also have a huge economic impact, Kearney argues.
“The International Energy Agency came out with a report that hypothesized that between now and 2035 there’s going to need to be about $17 trillion worth of investment to generate, transmit, and deliver electricity to a growing world. That’s all about this paradigm where we are delivering to meet peak demand,” he stresses. “In a world where we’re generating to meet average demand and using energy storage to deliver at peak times, you’re saving half of that money—between $8 and $9 trillion—and there’s the potential for adding a significant amount of renewable resources.”
“That’s the type of change that we’re talking about,” Kearney adds. “It’s full scale; it’s global; it impacts the environment; it impacts economics; and it paves the way for a significant amount of growth.”