2018 R&D 100 Award for High Voltage Electrolytes for Ultracapacitors

Ultracapacitors are energy storage devices capable of storing and quickly discharging large bursts of power but are limited by a narrow voltage window and low energy density.

ORNL researchers have developed a sodium-based electrolyte for ultracapacitors that extends the voltage window without side reactions and can double the specific energy while maintaining power density.

The breakthrough electrolyte is matched with special-made electrodes made of high-surface-area carbons bound with a stable polymer that won’t corrode in the new electrolyte formulation. The resulting combination enables a higher voltage device that necessitates fewer cells in a supercapacitor module, lowering costs while increasing module capacitance. It is also less toxic and more environmentally benign than traditional electrolytes, making it safer for grid storage and other low-cost, high-power energy storage solutions.

The ORNL development team, led by Jagjit Nanda, included Frank Delnick, Rose Ruther and Landon Tyler.

This project was funded by ORNL Seed Money, ORNL’s Laboratory Directed Research and Development Program and ORNL’s Technology Innovation Program.