Charged up: New polymer shows promise for storing energy

To the naked eye, it looks like clear plastic, but connect it to a bench-top multimeter and the digital readout that measures voltage begins to climb.

This is no piece of plastic. It’s among a new class of polymers that can maintain an electrical charge, potentially opening the door to a new, lightweight way of storing energy.

The material was developed by a team based at Clemson University’s Advanced Materials Research Laboratory and led by Marek Urban, the J.E. Sirrine Foundation Endowed Chair.

“Once the polymer is charged, it maintains the charge for a long, long time– we’re talking about three, four months, or possibly more,” Urban said. “This is something that does not involve any electrochemistry. It just involves design of the polymer, building from molecules that contain certain types of ions.”

While the material is still in the experimental stage, Urban sees broad commercial potential for anything that uses electricity — from portable batteries to charging devices. It could also be useful in quantum computing to enhance faster processing and quantum sensing.

“As far as manufacturing, it doesn’t need much, other than making the polymer,” Urban said. “These materials are stable to about 450 degrees Celsius. Mechanically, they are fairly stable. So there are a lot of advantages, as opposed to existing materials.”

The polymers would be less expensive than conductors such as lithium used in batteries, Urban said.

The material stores energy by polarizing cation-anion pairs inside the polymer when voltage is applied, separating them without triggering any chemical reaction. This separation creates a stable electric potential, held in place by ionic and van der Waals interactions within the polymer structure.

The research adds a new dimension to Urban’s body of work. Alongside his recent focus on energy-storing polymers, he has developed self-healing materials for applications ranging from scratch-resistant paint to longer-lasting batteries.

The team recently published its energy-storage findings in Angewandte Chemie International Edition, a journal of the German Chemical Society. The name of the article is “Electrical Energy Storage by Poly(ionic Liquids).”

The authors are Jiahui Liu, Tingwei Zhang, Sourav Biswas and Urban, all of Clemson’s Department of Materials Science and Engineering.