Thin, Flexible, Energy-Storing Glass Developed

A new type of glass — thin, flexible, and capable of storing energy at high temperatures (for use in high-power applications) — has been created by researchers at Penn State’s Materials Research Institute. The glass — which is about 1/10th the thickness of display glass — could prove very useful for a variety of applications in photovoltaics, EV power electronics, wind turbine generators, aerospace electronics, etc, according to the researchers. In particular, the researchers note that the glass may help to improve the affordability and reliability of future hybrid-electric and plug-in electric vehicles.

Flexible Glass Image Credit: Penn State Materials Research Institute

Flexible Glass
Image Credit: Penn State Materials Research Institute

While there are already a number of different thin and flexible glass types in use, this new glass is quite a bit different — possessing greater energy and power density, as well as a higher charge-discharge efficiency, even at rather high temperatures.

Penn State Materials Research Institute has more:

Researcher and lead author Mohan Manoharan and colleagues report on experiments with various alkali-free glass compositions and thicknesses, comparing their energy density and power density to commercial polymer capacitors currently used in electric vehicles to convert energy from the battery to the electric motor. Because polymer capacitors are designed to operate at lower temperatures, they require a separate cooling system and a larger safety factor, which adds to their bulk. In his research, Manoharan identified 10-micron thick glass from Nippon Electric Glass (NEG) as having an ideal combination of high energy density and power density, with high charge-discharge efficiency at temperatures up to 180 °C and, in more recent experiments, even higher.

Partnering with NEG leverages the investment of leading glass manufacturers in developing the processes to create continuous sheets of glass with less thickness and fewer defects. Working with State College-based Strategic Polymer Sciences, the researchers are developing the capability to produce inexpensive roll-to-roll glass capacitors with high energy density (35 J/cc3) and high reliability.

In work funded by the Department of Energy, Manoharan and the Penn State team led by Michael Lanagan, professor of engineering science and mechanics, are collaborating with Strategic Polymer Sciences to coat the glass with high temperature polymers that increase energy density by 2.25 times compared to untreated glass, and also significantly increase self-healing capabilities. Self-healing or graceful failure is an important consideration in applications where reliability is a critical factor.

“Postdoctoral researcher Mohan Manoharan unspools a ribbon of 10-micron-thick flexible glass used to store energy.”
Image Credit: Walt Mills, Materials Research Institute, Penn State

“These flexible glass capacitors will reduce weight and cost if replacing polypropylene capacitors,” Manoharan stated. “They could be used in any high energy density capacitor application — not only in electric vehicles, but in heart defibrillators or weapons systems such as the electric railgun the navy is developing.”

The new research was just published in the new journal Energy Technology.