When it comes to battery technology, most research focuses on extending battery lifetime. This makes sense, since for consumer electronics, electric vehicles, or home batteries, after safety, the top concern is avoiding frequent battery replacement. But unlike consumers, the Navy is willing to sacrifice battery lifetime in order to maximize the power they can store on ships for missions at sea.
For this purpose, David Wetz, a professor of electrical engineering at the University of Texas at Arlington, is investigating how batteries behave when they run at the highest rates. Over the years, his research on the thermal and electrical limitations of batteries has been supported by $1.5 million in grants from the Office of Naval Research (ONR). Backed by this funding, Wetz has worked on several projects relating to high-power batteries. He has designed and tested 1,000 volt direct-current batteries (both lead-acid and lithium-ion) for shipboard applications, studied the impact of high-pulsed magnetic fields on the corrosion rates of metallic alloys, developed a high power Hybrid Energy Storage Module, and studied the thermal properties of cylindrical lithium-ion batteries.
His latest research is supported by an $800,000 ONR grant to study batteries age when they run at high rates. “The keys for the Navy are safety, size and weight, due to the limited amount of room on a ship,” says Wetz. “To fit within the space, the batteries often need to be run at higher power to accomplish the mission even if that results in a slightly shorter battery lifetime.”
