Graduate student wins prestigious award for microbattery research

The Materials Research Society (MRS) honors a handful of students each year whose work in the field of materials science is considered exceptional. At the MRS fall meeting, MechSE graduate student James Pikul was given the gold award for the work he’s doing on microbattery research with his co-advisors, William King from MechSE and Paul Braun from Materials Science and Engineering. Pikul was one of nine students from around the world to win the gold award this year, including Chunjie Zhang, a MatSE student also advised by Braun.

Pikul received the award based on the new progress being made with his microbattery research—development of a primary (non-rechargeable) microbattery. Their previous iteration of microbatteries has impressive power density—density that’s superior to conventional lithium batteries—and energy density two times better than the best microbatteries previously presented, but still five times lower than the average cell phone battery. By changing the material chemistry and applying electro-deposition techniques, they have achieved a higher energy density while maintaining the power density they had previously demonstrated.

“We used a manganese oxide conversion compound, which in itself is unconventional, because typically this material is used for anodes and we used it for the cathode. Our voltage is between 1.5 and .5 volts, which is lower than the 1.8 volts required for most electronics. But we can do this now by using a boost converter that will up-convert our voltage to up to 5 volts at greater than 90% efficiency. Because of the advances in that field, we’re able to use a material that has a higher capacity but a slightly lower voltage. And that result was a higher energy density for our particular system,” explained Pikul.

Because their new microbattery is not rechargeable, it could present a variety of interesting applications, including short-life medical devices and disposable electronics. In these instances, “you can get a lot more energy and power if you use this kind of battery instead of a rechargeable battery,” said Pikul.

The next step for King’s group is to analyze the internal temperature and diffusion as well as electrical conduction through the materials of the battery system.

“The microbatteries we make right now are relatively thin, and they can scale into the third dimension easily without the physics changing. But the difficulty is in manufacturing them to get thicker microbatteries so you can have more energy density per area. That’s one of the next challenges we’re working on—how to get these electrodes thicker while still maintaining the same energy and power density to get a much better battery in the same area,” said Pikul.

The MRS gold award is well regarded in the materials field. Drawing an international audience of about 6,000, the MRS conference is the largest one focused on materials and the gold award is the best student award at the conference. To be considered for an award, a student must submit an abstract plus a personal essay, as well as a recommendation letter from his or her advisor. The 33 award finalists make a 10-minute presentation on their work, which factors into the judges’ criteria, alongside their academic level and project novelty.

In addition to the gold award, Pikul also won the MRS Science as Art silver award, given for incorporating creativity and artistic interpretation into a microscope image. Pikul’s art, titled “Down the Rabbit Hole: Adventures in Nanoscience,” depicts the material used to achieve his high-powered batteries. One of the electrodes cracked, leaving residue that happened to look like a rabbit. Some artful highlighting resulted in science as art that resembles a rabbit in a rabbit hole.