The Application Note “Demystifying Transmission Lines: What Are They, Why Are They Useful?” just published by Gamry Instruments is an introduction to Transmission Lines. It was written by Burak Ulgut.
Increasing world energy demand is one of the growing problems that researchers are tackling through new energy storage and conversion technologies. Porous electrodes offer a high surface area to volume or weight ratio which is highly beneficial to a number of energy generation or storage devices (e.g. Dye-Sensitized Solar Cells (DSC), Super-Capacitors(SC), Fuel Cells (FC), etc).
Electrochemical Impedance Spectroscopy (EIS) is a useful tool to extract various parameters out of complete devices. Due to the porous nature of the electrodes, distributed circuit elements (explained by the mathematics of transmission lines) have to be employed for proper modeling. Though transmission lines are commonly used, we had difficulty finding an introductory paper. Here we provide an introduction with invaluable help from two experts on the field, Prof. Juan Bisquert and Dr. Francisco Fabregat-Santiago of Universidad Jaume I in Spain.