A typical flexible ECG electrode is composed of certain types of polymers or elastomers that are made electrically conductive by the addition of fine carbon or metal powder. These electrodes are available with pre-pasted AgCl gel for quick and easy application on the skin using double-sided peel off adhesive type.
Related: Electrocardiogram (ECG)
The common type of biopotential electrode is the silver/silver chloride electrode (Ag/AgCl) which is formed by electrochemically depositing a very thin layer of silver chloride onto a silver electrode.
These electrodes recessed from the surface of the skin and imbedded in foam that has been soaked with an electrolyte paste to provide good electrical contact with the skin. The electrolyte-saturated foam also reduces motion artifacts that could be produced for instance, during stress testing when the layer of the skin moves relative to the skin surface of the Ag/AgCl electrode. This motion artifact could cause large interference in the recorded biopotential and, in extreme cases, could severely degrade the measurement made.
You can also read: Types of Biopotential Electrodes
