Editor’s Note: This story is part of “Meet a UChicagoan,” a regular series focused on the people who make UChicago a distinct intellectual community. Read about others here.
With over trillion tons of carbon dioxide currently circulating in the atmosphere and global temperatures should increase between 2 degrees and 9.7 degrees Fahrenheit over the next 80 years, the shift from fossil fuels to renewables is receiving critical attention. To effect this change, humanity will need entirely new methods of storing energy.
Current standard lithium-ion batteries rely on flammable electrolytes and can only be recharged about a thousand times before their capacity is significantly reduced. Other potential successors have their own issues. Lithium metal batteries, for example, suffer from short battery life due to long needle-like deformations called dendrites that grow whenever electrons shuttle between the anode and cathode of Li batteries. -metal.
For Chibueze AmanchukwuNeubauer family assistant professor of molecular engineering at the University of Chicago’s Pritzker School of Molecular Engineering, such tricky chemistry boils down to a flawed and often overlooked process: modern electrolyte design.
“The current approach to battery design, especially with electrolytes, works like this: I want a new property, I research a new molecule, I mix it up, and I hope it works,” Amanchukwu said. “But as battery chemistry constantly changes, it becomes a nightmare to predict which new compound you should use out of the millions of possible options. We want to demystify the dark art of electrolyte design.
Electrolytes are the third major component inside a battery – a specialized substance, often a liquid, that allows ions to move from anode to cathode. To function, however, an electrolyte must exhibit a long list of very specific attributes, such as proper ionic conductivity and oxidative stability, requirements that are made even more daunting by the millions of potential chemical combinations.
Amanchukwu and his team want to catalog as many electrolyte components as possible, allowing any researcher to design, synthesize and characterize a multifunctional electrolyte tailored to their needs. They liken the approach to a popular construction toy.
“The beautiful thing about Legos, and the aspect that we’re going to replicate, is the ability to build different structures from individual pieces,” Amanchukwu said. “You can use the same 100 Lego pieces to build any number of structures because you know how each piece fits together – we want to do that with electrolytes.”
How to catalog a million components
To create its electrolyte building blocks, Amanchukwu first turns to the archives. Scientists have been studying electrolytes for over a century, and their data is available to anyone who wants to skim through it.
Amanchukwu and his team use “natural language processing,” a type of machine learning program, to extract data from scientific literature. Once a few promising compounds are found, researchers synthesize them and test them with tools like nuclear magnetic resonance (NMR), a cousin of MRI, to better understand their properties and refine them even further.
Once tested, the compounds are placed in real batteries and studied again, and the resulting data is then fed back into the system.
The end result is a database of electrolytic components that can be easily combined as needed. Such a system would dramatically speed up the development of new batteries, but its impact would be felt even beyond that.
Carbon capture technology currently relies on electrolytes in two ways. During the capture phase, an electrolyte acts as a solvent to help separate the carbon dioxide from the air, and later a second electrolyte helps convert the C02 into a usable product like ethylene.