Phil Allison wrote:

** The ESR of an electro cap is mostly due to the conductivity of the
liquid electrolyte used inside.

Modern, water based electrolytes have much better conductivity and
hence lower ESR values compared to the same size caps made in the
past and so can handle higher operating currents without excessive
self heating.

What time frame do you mean by "modern" as opposed to "past?"

When motherboard caps fail long after the "plague" was over, is it
mainly due to the voltage being under-rated?


Heat is the main killer of electros, whether from the local ambient
temp or current flow in the cap or both. Luckily, the conductance of
electrolytes improves with increasing temp which helps extend their
life in SMPS.


... Phil

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