How Electrodes Are Used in Many Industrial Applications

Electrodes are conductors through which an electric current enters or leaves a material, substance or a vacuum whose electrical characteristics are being measured, used or manipulated. Terminal points in electrical components such as transistors, diodes and batteries are all common examples of an electrode with which most people will be immediately familiar.

In an electrochemical cell, these terminal points are referred to as either anodes or cathodes - the anode is the point at which electrons leave the cell and oxidation occurs. The cathode is the point at which electrons enter the cell and reduction occurs. Each of these points may become either the anode or the cathode depending on how the voltage applied to the cell. Bipolar electrodes function as the anode of one cell and the cathode of another cell.

In arc welding, an electrode is used to conduct current through the work pieces to fuse the two pieces together. Depending on the process, the electrode is either consumable, such as in the case of gas metal arc welding or shielded metal arc welding, or non-consumable, as in gas tungsten arc welding. For a direct current system the weld rod or stick may be a cathode for a filling type weld or an anode for other welding processes. For an alternating current arc welder, the welding electrode is not considered to be an anode or cathode.

As you may have guessed, electrodes are also used extensively in the sciences, with materials analysis and the life sciences both making use of these versatile electrochemistry tools. Since they are invariably part of instruments which measure electrical charges of materials, analytes and other samples, they are used in a wide variety of different instruments across an even wider range of applications in the laboratory and in portable instruments which can be taken into the field or onto a production floor for quality control purposes. Electrodes are also an essential component of any instrument used for conductivity testing, impedance testing and similar applications.

Electric currents are sometimes run through nonmetallic objects to alter them in numerous ways and to measure conductivity for various purposes. Some examples include EEG, ECG, ECT and defibrillators in the field of medicine, brainwave detection, electrophysiology applications in biomedical research facilities, electrochemical analysis and electrolysis, to name only a few of their many different uses.

Electrodes are also used in electrochemiluminescence, which is a useful technique for analytical purposes where the easier reaction control offered by the ability to apply electrode potential is desirable. This makes the technique an improvement over chemiluminescence without the use of an electrode, at least for certain applications where higher sensitivity is an asset to the analytical process.

The list of applications above barely scratches the surface. The use of electrical energy in our homes, consumer goods, medical devices, scientific instruments and an enormous number of other products which are an indispensible part of modern life would be unthinkable in their absence. Electrodes are something with far too many uses to list; even if your career doesn't involve any sort of work in the laboratory, you have plenty of reasons to be thankful for their existence.