leading cause of failure in lithium-ion batteries used to power electric cars are dendrites – tiny pieces of lithium that break away during charge/discharge cycles, bridging the positive and negative sides of the battery. Tasked with finding a solution to that long-standing problem is Donghai Wang, associate professor of mechanical engineering at Penn State University.
Wang recently won a $1.1 million U.S. Department of Energy Vehicle Technologies Office grant to develop lithium-ion conductor technologies to protect battery metals so lithium won’t chip off and form dendrites. Wang leads the Energy Nanostructure Laboratory, which focuses on nanomaterial development for clean energy technologies, such as batteries, solar cells, fuel cells, and environmental remediation.
With the funding, Wang’s team will use thin layers of material – nanostructured hybrids – to shield battery components. Batteries consist of a positive side (cathode), and a negative side (anode), separated by a liquid electrolyte. Dendrites typically form on the anode, eventually infiltrating the electrolyte and bridging to the cathode, causing short circuits. The results can be overheating and even fires, as seen recently with some smart phones.
Wang seeks to develop a protective coating of self-formed hybrid conducting layers that will prevent dendrite formation by separating the anode from the electrolyte. Wang believes protecting the anode will lead to a safer, lighter, and more powerful and efficient electrical vehicle battery. He will then test his new system and compare its performance with present-generation electric vehicle batteries.
“Our group is very excited to have received this award and to work on this critical and challenging advancement to improve the performance of lithium batteries,” Wang says.
Wang’s project was one of 35 chosen for funding in 2016 by the Vehicle Technologies Office. Funded projects aim to reduce the cost and improve the efficiency of plug-in electric, alternative fuel, and conventional vehicles and most will support the goals of EV Everywhere, an effort to make plug-in electric vehicles as affordable and convenient as gas-powered vehicles by 2022.
Penn State University Energy Nanostructure Laboratory
U.S. Department of Energy Vehicle Technologies Office