A solid electrode refers to a stable and unchanging electrical conductor. It is a material that can conduct electricity consistently without changing or breaking down easily. Full definition
This concept involves the replacement of solid electrodes with energy - dense liquids. (jcesr.org)
At that time, the chemical solutions of opposite charge can be pumped across solid electrodes, thus creating an electron exchange that provides power to the electrical grid. (rochester.edu)
So University of Wisconsin, Madison, engineers Tom Krupenkin and J. Ashley Taylor decided to try doing away with one of the solid electrodes and replacing it with an electrically conductive liquid. (sciencemag.org)