Hybrid EIS

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Hybrid EIS

Description

The Electrochemical Energy Hybrid EIS technique is used to characterize the electrochemical interfaces within an energy device or cell. It is especially useful when the potential of the interface is changing with time and the interfacial impedance is strongly dependent on the measurement frequency. A small-signal AC-current excitation is applied to an electrochemical cell. The phase-sensitive AC response of the interface is measured as the frequency of the excitation signal is varied. The magnitude of the AC current is adjusted to obtain a nearly constant AC-potential level.

 

The Hybrid EIS technique can be useful many areas of electrochemistry, including research in batteries, electrode kinetics, and industrial electrolysis.

 

The output of an EIS experiment is a complex impedance spectrum. The term complex is used in its mathematical sense: containing both real and imaginary terms. An EIS spectrum is usually graphed as either a Bode plot (Impedance magnitude and phase plotted versus frequency) or a Nyquist plot (imaginary impedance plotted versus real impedance). Analysis of the impedance spectrum can give you the following information:

 

Polarization resistance

Double-layer capacitance

Solution resistance

Mechanistic and kinetic information

 

This is a half-cell, full-cell, stack, or dual-electrometer experiment. Dual-electrometer mode is only available with the Interface 5000.

 

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