Most people see defects as flaws. A few Michigan Technological University researchers, however, see them as opportunities. Twin boundaries -- which are small, symmetrical defects in materials -- may present an opportunity to improve lithium-ion batteries. The twin boundary defects act as energy highways and could help get better performance out of the batteries.

Lithium-ion batteries are lightweight, pack a whopping punch of energy density, and their efficiency continues to climb. Like all basic batteries, ones run on lithium ions rely on shuttling ions from one place to another. Technically speaking, that's between the anode and cathode, and an electric current coaxes ions to shuffle between them. A low battery means there is less exchange happening between the anode and cathode. Twin boundaries could help hustle that exchange along or perhaps extend it, hopefully without losing battery life.

The research team examined twin boundaries in tin oxides. It's applicable in many battery materials. The next step is finding out how to optimize these defects to balance the mechanical integrity with the amount of twin structures. Finding that balance will be the focus of the researchers' next steps, and this new finding about twin boundaries lays the groundwork for improving lithium-ion batteries.