Super capacitor from tea leaves and molasses | Sunday Observer

Super capacitor from tea leaves and molasses

Meghana Bollimpalli won one of the top three prizes at the Intel International Science and Engineering Fair for presenting on the low-cost supercapacitor project
Meghana Bollimpalli won one of the top three prizes at the Intel International Science and Engineering Fair for presenting on the low-cost supercapacitor project

The summer before she entered eighth grade, Meghana Bollimpalli visited family in India, traveling with her politician grandfather to rural communities and witnessing how different life was there compared to her home in Little Rock, Arkansas. At the time, she had no idea that experience would set her on the path to work on an accessible supercapacitor that earned top honors at a national science fair in 2018. She simply wanted to help.

“People in these communities have to walk four miles every single morning to get water that wasn’t even clean,” Bollimpalli, now a high school senior at Little Rock Central High School, tells Inverse. “Seeing this, and seeing all the health issues that were coming from waterborne illnesses, I was really impacted by that. I guess I always knew that not everyone in the world had access to clean water, but I didn’t know how bad it was until I actually saw it.”

She went on to design a cheap water filter made from sawdust, coffee grounds, and terra cotta that she distributed among rural communities in India — her effort to help some of India’s 163 million people who lack access to safe water. “Seeing that, I was like, ‘Oh my god, I actually did something that really impacted someone’s life,’” she says.

Now, five years later, she’s continuing her mission to address scientific issues with economically feasible solutions by applying her ingenuity to supercapacitors, the tiny, unbelievably expensive electronic devices that store massive amounts of electrical energy and have the potential to make a huge clean energy impact. (“Every year, I just pick a different topic in environmental science to do research on,” she says.) Her project — a far cheaper and wildly inventive version of the pricey device — secured second place and the Young Scientist Award at the Intel International Science and Engineering Fair in October 2018.

To Bollimpalli, the connection between supercapacitors and the lives of average people is clear. Limited energy storage capacity is one of the major obstacles stopping people from more widely adopting alternative energy sources like solar- and wind-generated electricity. If scientists can find cheaper, easier ways to store the energy generated by renewable sources, then the world will have a clearer path to adopting non-petroleum energy.

However, as she learned, supercapacitors are not cheap.

“To actually get a supercapacitor to work, it needs an electrode, and these electrodes are thousands of dollars because they’re made from things like platinum, palladium, gold, and diamonds,” Bollimpalli says. “So looking at that, and seeing how applicable they already were, I wanted to find some way to cut the cost of the electrodes to make supercapacitors even more applicable and revolutionise their applications within the energy industry.”

In the search for people working on cheaper supercapacitors, she found herself in the lab of Noureen Siraj, Ph.D., an assistant professor of chemistry at the University of Arkansas, Little Rock. One of Siraj’s students, Samantha Macchi, had already been working on such a project for about a year and a half, figuring out how to make supercapacitor electrodes from common materials like used tea leaves, molasses, and a basic kitchen microwave oven — humble beginnings for a high-tech device. Siraj and Macchi brought Bollimpalli into the project to learn about the work, which she later presented at ISEF. Meanwhile, Macchi and Siraj published the resulting research in January in the journal Chemistry Select..

Bollimpalli was initially assigned to a different project in the lab, but when she found out about the work on supercapacitors, she asked to switch tasks. Siraj, who is used to having high school students learn about her team’s work, quickly obliged.

“She quickly learned all the protocols, and she actually was able to explain. She brought an understanding that is missing in a lot of the high school students,” Siraj tells Inverse. “She really is good at absorbing the information.” They worked together tirelessly to help Bollimpalli nail the presentation she would later give at ISEF.

“She practiced with me so many times, and I know that she understood the material,” recalls Siraj.

Although she’s known it since her return from that summer in India, Bollimpalli left Siraj’s lab and the ISEF experience with an even deeper understanding of how scientists should think if they want to change the world for the better.

“This was a connection that I kind of recognized through my research,” she recalls. “Whenever you do research, you have to make sure that your research is both scientifically feasible and economically feasible because if the product that you’re making or designing isn’t cheap, nobody’s going to use it. It has to be a part of the economy that already exists.”

Moving forward, Bollimpalli hopes to bring her understanding of the economic realities of science into her higher education and beyond. She’s been accepted to Washington University in St. Louis, where she plans on double majoring in environmental chemistry and economics. After college, she says she wants find work that allows her to pursue science that addresses economic realities.

“I’m really interested in finding ways to connect economics and science.”