The Future of Grid Energy Storage Starts Today

Although lithium-ion has been a favorite for a long time, PNNL researchers are studying different kinds of materials, such as sodium-ion, nickel-iron, or lead-acid, that could be scaled up to cost-effectively provide electricity for longer periods of time for the grid—a concept known as long-duration energy storage. Testing these new technologies helps optimize performance, which is critical for commercialization and eventual public adoption.

At GSL, researchers will be able to increase the number of tests performed and the size of battery that can be tested. These expanded capabilities will also directly support DOE’s Long Duration Storage Earthshot, aimed at delivering 10 plus hours of storage at 90 percent of today’s cost within the next decade.   

Using Artificial Intelligence and Machine Learning to Advance Technology
It’s not just the number of individual materials that need to be tested. In some cases, a molecule’s structure can affect its behavior, so scientists also need to test different structures of molecules to understand their effectiveness as storage materials.

For instance, PNNL is investigating a novel battery technology called organic-flow, which employs organic molecules dissolved in a liquid electrolyte. For a flow battery to work, the molecules that shuffle electrons must be soluble so they can dissolve into the liquid. But solubility is an elusive characteristic to study, said Wei Wang, a materials scientist at PNNL. So researchers have to test many different molecules and their solubility to find out which would best work in a flow battery.

Moreover, multiple organic molecules can have the same core structure, but different subgroups of atoms attached. “For each molecule, there’s potentially thousands of different variations. How do you know which you should work with? The scale of the problem is astronomical,” Wang said.

Investigating each molecule and its many different variations is costly and time-consuming, so PNNL researchers are working on a solution called the digital twin battery—a machine-learning model that can simulate a battery’s behavior so researchers can plug in digital versions of the molecules to test. With a digital model that uses artificial intelligence, scientists can test the characteristics of a targeted organic molecule (and each of its variations) at an accelerated speed and reduced cost. GSL will enable researchers to study different materials in larger batteries, providing Wang and his team the mountains of data needed to build the battery digital twin model.

Safety First
With any new technology, researchers must anticipate and prepare for potential safety hazards. Large energy storage systems that support the grid come with their own risks, so PNNL is supporting the development of a unique set of safety standards to guide manufacturers in designing and installing safe systems. The GSL building, for instance, will be equipped with safety features to keep researchers and the laboratory safe should a large energy storage system fail.

PNNL is also dedicated to the safety of the communities that end up using this technology.

Energy storage systems consist of “a bunch of batteries assembled together with a battery management system, some kind of thermal control like air conditioning, communications components, converters that change the current from direct to alternating current, and more, ” said PNNL advisor Matthew Paiss. This complexity offers a level of safety built in but because of that same complexity, “the failure risk makes it a potentially more significant incident,” he continued.

Paiss is a former firefighter who specializes in energy story system safety. He travels around the country educating battery manufacturers, city leaders, and firefighting teams on how to best handle emergencies like battery fires. GSL will be central to developing energy storage safety courses geared toward local community stakeholders, such as firefighters, rescuers, and other first-responders.

“We’re really just at the tip of the iceberg of seeing what opportunities we can offer. We want to bring people to GSL and help educate them on all aspects of battery life, whether they manufacture batteries or not,” Paiss said.

The Future of Energy Storage
At GSL, researchers like Reed and Wang and safety advisors like Paiss will be able to collaborate on understanding emerging battery technologies to help accelerate a decarbonized future. The new facility will also help foster collaborations with industry partners who are working on challenges related to long-duration energy storage.

“Some of the problems with batteries don’t emerge until you size up to a certain scale, like the scale needed for an energy storage system to support the grid,” Sprenkle said. “To solve long-term energy storage challenges, we’ve got to get all the stakeholders on the same page. GSL will be a focal point for those collaborations.”

JoAnna Wendel is a media relations specialist at the Pacific Northwest National Laboratory (PNNL). The article was originally posted to the website of PNNL.