How does excessive ripple current degrade electrolytic capacitors? What processes are involved and how do they work?

How does excessive ripple current degrade electrolytic capacitors?

Ripple current causes heat to be generated within the capacitor and electrolyte capacitors degrade faster at higher temperatures.

Why does ripple current cause heat?

In general a capacitor will heat up due to its ESR alone. With ripple current involved, there is additional heating due to the dielectric losses caused by the changing field strength.

Why degrade electrolyte capacitors faster at high temperatures?

During the lifetime of the electrolyte capacitor, the electrolyte evaporates. Heat accelerates this phenomenon. Runaway failure is possible because degradation can increase ESR and this further increases heat dissipation and temperature.

protected by Kortuk Nov 13 '13 at 19:47

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.