Indium for lithium battery anode makes fast charging a reality; Cornell researchers look for lighter alternatives.

Engineers at Cornell University have developed a lithium battery capable of charging in less than five minutes, with stable performance over extended cycles of charging and discharging. The secret ingredient? Indium.

"Range anxiety is a greater barrier to electrification in transportation than any of the other barriers, like cost and capability of batteries, and we have identified a pathway to eliminate it using rational electrode designs," said Lynden Archer, professor and dean of Cornell's College of Engineering, who oversaw the project and helped co-author the paper. "If you can charge an EV battery in five minutes, I mean, gosh, you don't need to have a battery that's big enough for a 300-mile range. You can settle for less, which could reduce the cost of EVs, enabling wider adoption."

The team's paper, titled Fast-charge, long-duration storage in lithium batteries, has been published in the journal Joule. The study identified indium's two notable characteristics as a battery anode: low migration energy barriers and moderate exchange current density, facilitating rapid ion diffusion and efficient surface reactions essential for quick charging and long-term storage.

"The key innovation is we've discovered a design principle that allows metal ions at a battery anode to freely move around, find the right configuration, and only then participate in the charge storage reaction," Archer said. "The end result is that in every charging cycle, the electrode is in a stable morphological state. It is precisely what gives our new fast-charging batteries the ability to repeatedly charge and discharge over thousands of cycles."

The U.S. Department of Energy's Basic Energy Sciences Program supported the team's research through the Center for Mesoscale Transport Properties – an Energy Frontiers research center. Resources were also utilized through the Cornell Center for Materials Research, funded by the National Science Foundation's Materials Research Science and Engineering Center program.

The researchers used a chemical engineering concept called the Damköhler number to study the battery's performance – a calculation used in chemical engineering to relate the chemical reaction rate to the exchange of mass, energy, charge, and momentum occurring in a system.

"While this result is exciting, in that it teaches us how to get to fast-charge batteries, indium is heavy," Archer said. "Therein lies an opportunity for computational chemistry modeling, perhaps using generative AI tools, to learn what other lightweight materials chemistries might achieve the same intrinsically low Damköhler numbers. For example, are there metal alloys out there that we've never studied, which have the desired characteristics? That is where my satisfaction comes from, that there's a general principle at work that allows anyone to design a better battery anode that achieves faster charge rates than the state-of-the-art technology."