The swelling of electrolytic capacitors is usually associated with a disruption in the structure of the electrolyte inside the capacitor. Electrolytic capacitors have two electrodes separated by a layer of electrolyte. When the capacitor is connected to a voltage source, potential differences appear on the electrodes and current begins to flow through the electrolyte.
The causes of swelling can be the following factors:
- Overheating: high temperatures can cause the electrolyte to evaporate and reduce its volume, which leads to a decrease in capacitance and an increase in internal resistance.
- High voltage: exceeding the nominal voltage can cause insulation breakdown between the electrodes and lead to electrolyte leakage. As a result, the volume of the electrolyte decreases, leading to swelling.
- Wear and tear: over time, the electrolyte in the capacitor can break down into components, which leads to a decrease in capacitance and an increase in internal resistance. This may be due to improper use of the capacitor, a mismatch in nominal value, or low-quality materials.
- Polarization: incorrect connection of the capacitor to the power source can lead to its polarization, which causes insulation breakdown and electrolyte leakage.
In any case, the swelling of an electrolytic capacitor can lead to its failure and potential damage to the circuit in which it is used. Therefore, it is recommended to periodically check capacitors for swelling and replace them as needed.
