Mechanical engineering researchers uncover ways to improve the safety of lithium-ion batteries

Elham Sahraei at crash of Tesla Model S.

Elham Sahraei, an assistant professor in the Department of Mechanical Engineering, (left) and postdoctoral student Golriz Kermani, are pictured here at the Insurance Institute for Highway Safety in Ruckersville, Virginia, after the crash test of Tesla Model S. They are researching lithium-ion batteries used in fully electric vehicles.

Elham Sahraei is using experimental and computational methods to analyze the integrity of lithium-ion batteries under various conditions.

Mason Engineering scientists are uncovering ways to improve the safety of the lithium-ion batteries—work that could one day save lives.

The batteries made headlines in recent years because of fires in the Tesla Model S and the Samsung Galaxy Note 7 smartphones.

The danger with lithium-ion batteries—used in fully electric cars, cell phones, laptops, drones, ships, submarines, airplanes, and buildings—is there’s a lot of energy in a small package, and if that energy is released suddenly it can cause a fire, and in extreme cases, it could cause an explosion, says Elham Sahraei, an assistant professor in the Department of Mechanical Engineering and a Beck Faculty Fellow.

Sahraei and fellow researchers at Mason’s Electric Vehicle Safety Laboratory are using experimental and computational methods to analyze the integrity of lithium-ion batteries under various conditions. Their research examines what happens if the battery is physically damaged in an accident.  “We have discovered that mechanical failures correlate with electric internal short circuits,” she says.  

In the lab, they test the batteries to characterize their material properties and failures. Then they develop computer models to simulate the behavior of the battery. There aren’t any comprehensive models in the literature right now. 

Car companies and battery companies can use these computer models to optimize the protective structure around the batteries so they have the lowest weight and highest protection. Eventually this work could save lives, she says.

Oscar Barton Jr., chairman of the Mechanical Engineering Department, says, "Dr. Sahraei's novel research studying vehicle battery safety places her in a select group of researchers nationwide who are studying this topic. Her expertise will help shape the department's cutting-edge, multidisciplinary research portfolio designed to meet the technological challenges facing society."

The research is important to many players, says Sahraei, who is also a research scientist at the Impact and Crashworthiness Lab at the Massachusetts Institute of Technology.

Mason’s Electric Vehicle Safety Laboratory has received funding from the Office of Naval Research and MIT Battery Consortium (Daimler, Jaguar/Land Rover, LG-Chem, Boston Power, PSA Group, Altair, and AVL).