The Trienens Institute Transform Pillar
Nov 19, 2024 9:15 AM
One of the Trienens Institute Six Pillars of Decarbonization, the Transform pillar will transform the processes used to create fuel and chemicals to reduce or remove carbon
The Trienens Institute Store Pillar
Innovating for large scale renewable energy storage
Julianne Beck | January 15, 2025
Lights glow inside homes on a cold winter evening as the sun sets over the neighborhood. Indoors, family members go about their evening tasks, cooking, reading online, posting photos to social media, and even streaming a movie while the furnace warms the home. This series of routine activities would not be possible without a durable utility that provides energy to the home and its many systems.
Today, most of our energy is derived from fossil fuels such as coal and natural gas—two resources that are finite in supply. These fossil fuels also release carbon dioxide, one of the most prevalent greenhouse gases contributing to climate change. As our global energy demands grow with evolving daily needs and the rise of energy intensive technologies such as data centers, researchers at Northwestern are contributing to the development of alternate, renewable energy systems that can supplement and perhaps replace today’s dominant energy sources. Unlike fossil fuels, solar and wind are energy sources that will not run out.
“We need to move to a form of energy that can be renewed and does not depend on a finite supply of fossil fuels. The primary renewable energy options are solar and wind. Those technologies have recently become cost competitive with coal, gas, and oil,” said Mark Hersam, Chair of Materials Science and Engineering at Northwestern and the Walter P. Murphy Professor of Materials Science and Engineering.
Together, Hersam and Jeff Lopez, assistant professor of chemical and biological engineering, serve as co-chairs of the Store pillar, one of the Trienens Institute Six Pillars of Decarbonization. The pair is leading interdisciplinary research efforts to facilitate a large-scale deployment of renewable energy sources in the energy grid. Their aim is to pioneer new materials with high performance and low cost to unlock a new generation of scalable grid storage.
“We’re looking at this from two perspectives: can we take existing chemistries and make them cheaper, either through manufacturing or materials innovation; and can we go after truly new, longer-term technologies,” explained Lopez.
Renewable energy sources are already part of the electric grid, currently providing over 20% of all electricity, according to the Department of Energy. That is especially true in places like California, where solar energy is abundant and broadly deployed during the sunniest time of day. Yet, energy from solar and wind are intermittent and require storage for use at times when they are not naturally occurring. Even though renewables are being incorporated and even stored at relatively small capacities said Hersam, “the question is how quickly and widely can we accelerate the adoption of large-scale energy storage technologies throughout the grid.”
How can we store renewable energy at a low cost?
The Northwestern University researchers are considering batteries and other stationary energy storage options. Their work builds on past success in the field.
In the early 2000’s, Harold Kung, Walter P. Murphy Professor Emeritus in the McCormick School of Engineering, developed technology that incorporated silicon (which is found in sand) with graphene to increase the energy storage capacity of lithium ion batteries. The work in his lab led to the launch of a company, now called Nanograf, which is in the process of commercializing this proprietary technology
Today, lithium-ion batteries are the most common type of battery used to store energy in everything from smartphones to electric vehicles to the electric grid. Yet, lithium, nickel, and cobalt are finite resources and presents complex supply chain issues. In addition, “commercial lithium-ion battery materials, such as graphite, NMC [nickel manganese cobalt oxide cathode], and LFP [lithium iron phosphate cathode], are operating at the edge of their theoretical performance,” said Lopez. “There’s no more room to squeeze increased energy density out of these materials. If we want to do any better on performance or cost, we have to move to other materials.”
The Northwestern researchers are focused on finding solutions either through the development of new manufacturing approaches or new materials. “Utilizing materials that are more abundant and more geographically distributed can mitigate a lot of supply chain issues that occur when a technology is deployed at the largest of scales,” explained Hersam. Benefits include minimizing the current need for battery materials based on critical minerals like cobalt, which is limited in supply, and nickel. On a larger scale, “we’re especially excited about lowering the carbon footprint of manufacturing, which in turn lowers cost because you are paying less in electricity to manufacture the cells,” said Lopez. Next generation battery materials for storage could include sodium, zinc, aluminum, as a potential replacement for lithium or manganese and iron, potential replacements for cobalt and nickel.
While the materials used in batteries are of high importance, the molecular chemistry is also an essential component. It affects the lifespan of a battery, which can lose its ability to hold charge following extended use due to various internal chemical processes that wear on it over time.
Hersam’s lab is studying strategies for replacing cobalt with manganese in lithium-ion batteries due to its higher abundance and lower cost, which requires stabilizing manganese-based materials that are more susceptible to degradation than cobalt. Towards this end, Hersam has found success in using graphene as a chemically inert coating on manganese-based battery materials. His findings have been transitioned to a startup company called Volexion, which is now working on scaling up the production and deployment of this technology.
What is next for grid scale energy storage?
In addition to improving upon existing technologies, new energy storage technologies are in development in Northwestern University labs and in collaboration with partners.
Hersam’s lab is developing the components of next generation batteries by working to perfect the use of solid electrodes as a replacement for the volatile and flammable liquid electrodes found in lithium-ion batteries today. This is an especially important factor for batteries that will be used on larger scales in the future. “Solid electrolytes are a next-generation family of materials emerging from the Store Pillar that has commercial potential for improving battery safety, thereby enabling higher energy density and broader deployment of battery technology,” said Hersam.
Christian Malapit, assistant professor of chemistry, has been innovating to more efficiently power a redox flow battery, which is a type of battery that is powered by organic compounds or metal-based solutions. The effort is geared towards the use of organic waste products, converting them to compounds that can store energy in a grid scale. Some of Malapit’s next steps will be supported through the Store pillar.
How partnership fuels innovation
Both within the university and beyond, collaborations have been key to the development of improved technologies and will continue to be in the future. The faculty credit the collegial culture of Northwestern, from students to postdoctoral researchers to staff and faculty, for facilitating productive interactions that accelerate the pace of research.
“There is this community of materials scientists and chemists and engineers who have been contributing to this field for a very long time and pushing the foundation forward,” noted Lopez, who is also eager to partner with faculty in business, economics, and related fields. “When we put these folks together in the same room there’s an opportunity to get everyone speaking the same language to work towards a solution more quickly, and to identify some big economic levers that we can then pull on with technology coming out of the lab.”
In addition, university facilities are also critical. Northwestern has long been a leader in materials science and maintains top-tier laboratory facilities that are enhanced by additional resources such as at the nearby Argonne National Laboratory.
The newest university laboratory facility addition occurred this month, when the Trienens Institute added equipment to support battery production at a larger and more commercially relevant scale than is possible in a typical university laboratory. According to Lopez, this will accelerate the ability of researchers to prepare their discoveries for large-scale adoption by scaling up 1,000 times from coin cell batteries to a pouch cell battery. The equipment will be open to internal and external users in the current GIANTFab facility.
When such discoveries are ready for the next step, Northwestern’s Innovation and New Ventures Office (INVO) provides services for researchers to evaluate and advance their inventions. This includes the Trienens-Q Cleantech Accelerator, a program that eases the transition from invention to commercialization. Hersam is currently working with the accelerator to advance his work with solid electrolytes.
Along the way, partnership with corporations and utilities is imperative, and funding from a range of sources helps to accelerate the pace of the work. Ultimately, that could mean more collaboration with utility companies to support the emerging electric vehicle industry in the Midwest and beyond.
Looking ahead, Hersam and Lopez are hopeful for the future – both as a result of the dynamic student population they work with today, but also because of the potential for great discoveries when interdisciplinary teams come together.
The Store pillar intersects with the work of several others among the Trienens Institute Six Pillars of Decarbonization and the varied expertise of their teams. “We’re building this community where everybody has the same high-level goal—and we’re all moving in the same direction with different expertise and different specializations—I think that sets us up for success,” said Lopez. “The pillar has been hugely enabling. It’s been very exciting to have the support... I think we’re seeing just the beginnings of a lot of growth in this space at Northwestern and so that’s very exciting.”
Harold Kung and Mark Hersam have a financial interest in and affiliation with Nanograf. Northwestern University has financial interests (equities, royalties) in Nanograf.
Mark Hersam has a financial interest in and affiliation with Volexion. Northwestern University has financial interests (equities, royalties) in Volexion.