The corrosion situation of a metal is caused by the electrochemical potential at which it is found in a certain medium. The conceptual solution would be to bring the metal to a potential of immunity or passivity where it does not dissolve in its ions.

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Cathodic protection of a specific metal consists of lowering the (more negative) potential of the metal to be protected.

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​Marine Corrosion

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​In the sea, for example, a steel hull made up of 95% iron (Fe) is affected, among other corrosive mechanisms, by the reduction of oxygen in so-called cathodic zones, which provide an attraction for the electrons of the iron, which, when released, cause oxidation of the metal, decomposing its structure and altering all its mechanical properties.

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The corrosion of a metal is determined by the electrochemical potential at which it is found in a given medium. The conceptual solution would be to bring the metal to a potential of immunity or passivity, where it does not dissolve in its ions.

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Cathodic protection of a given metal consists of lowering the (more negative) potential of the metal to be protected below a value defined for each metal, in which corrosion cannot occur thermodynamically. Below this value, electrochemical corrosion is eliminated.

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​Impressed Current Solution

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​If we limit ourselves to applying a negative current to the metal to be protected and a positive current to the electrolyte (that is, seawater), we will achieve the same effect: lowering the potential of the metal to be protected until it reaches its immunity potential, without the need for sacrificial anodes; only the battery current is applied. Therefore, we have protected the ship's hull metal with the impressed current system, just as the anti-corrosion equipment does.