
320 Fuel Cells
8.2.2 Electrochemical Impedance Spectroscopy
It is well known that electrical resistance is the ability of a circuit element to
resist the ow of electrical current. For a ow of DC current i to an applied
DC potential E, the resistance is given by Ohm’s law as
R
E
= . (8.2)
However, in the real world, circuit elements exhibit much more complex
behavior; the simple concept of resistance cannot be used and in its place, imped-
ance, a more general circuit parameter, is used. Like resistance, impedance is the
ability of the system to impede the ow of electrical current through it. Though
it is similar to resistance, impedance is ...