Electrolytic capacitor development

What is an electrolytic capacitor?

An electrolytic capacitor is a polarized capacitor whose anode or positive plate is made of a metal that forms an insulating oxide layer through anodization. This oxide layer acts as the dielectric of the capacitor. A solid, liquid, or gel electrolyte covers the surface of this oxide layer, serving as the cathode or negative plate of the capacitor.

How to estimate the life of an electrolytic capacitor?

In order to estimate the remaining life of electrolytic capacitor, a model that can characterize the system is presented in a first part. Thus, a low-cost It has been seen that normal use leads to the evaporation of the electrolyte and the repair of the oxide layer.

What are the mechanisms and failure modes of an electrolytic capacitor?

Mechanisms and failure modes according to the stress in an electrolytic capacitor. A normal use of the capacitor leads to the evaporation of the electrolyte and the repair of the oxide layer. These are two causes of electrolyte disappearance, which is the main cause of capacitor degradation under normal conditions.

What model is used for electrolytic capacitors?

The most commonly used model for electrolytic capacitors is based on Arrhenius' law, which describes the influence of the constraints related to the ambient temperature and the current flowing through the capacitors, and on the Coffin-Manson empirical law for the consideration of the applied voltage.

How does electrolyte affect the capacitance of a capacitor?

The electrolyte must adhere to the whole surface of the anode and cathode foils to have a higher capacitance. It can also repair defects in the anode oxide film as seen before. The nature of the electrolyte influences the temperature and frequency characteristics response of the capacitor (Fig. 4. 5).

What is a dry type of electrolytic capacitor?

This type of electrolytic capacitor combined with a liquid or gel-like electrolyte of a non-aqueous nature, which is therefore dry in the sense of having a very low water content, became known as the "dry" type of electrolytic capacitor.