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Updated: Jan 30, 2026

In Situ Lithiated Reference Electrode: Four Electrode Design for In-operando Impedance Spectroscopy
Published on: September 12, 2018
A Practical Approach to Electrode-Skin Impedance Unbalance Measurement
Abstract:
Unbalance between electrode-skin impedances is a major problem in biopotential recordings, leading to increased power-line interference. This paper proposes a simple, direct method to measure that unbalance at power-line frequency (50-60Hz), thus allowing the determination of actual recording conditions for biopotential amplifiers. the method is useful in research, amplifier testing, electrode design and teaching purposes. It has been experimentally validated by using both phantom impedances and real electrode-skin impedances.
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