Question capacitor

What recommendations on how to prevent deformation of the dielectric layers in aluminum electrolytic capacitors from stored electronic devices that were manufactured in the early 90s and early 2000s and store in my home at a temperature of 33-36C, humidity 57-67% and energized devices at 220v AC 60hz?

Replace them? I did that (locate equivalents, unsolder old, solder in new) on a couple of devices which came back to life; so satisfying.

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There is no preventing this, like @jlittle said, replace them.
Especially tantalum caps, they will short out!

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Yeah the problem is that electrolytics dry out They contained an oil impregnated paper film.
Once they dried out they simply became resistive and the heat caused them to bulge or often explode.
Tantalums however when the experience severe overvoltage will explode leaving an awful stench that persists for days! ( dont ask how i know this🤣)
Wifey gets mad enough when an led fries​:rofl::rofl::rofl:

For reference on how fast capacitors can degrade, I attempted to repair the power supply of an Orico hdd enclosure that stopped working and found 2 budging capacitors (one actually had a rupture but I knocked off the electrolyte before taking the picture):

What the capacitance ended up being after degradation:

The caps have a mid-2013 date code on them and I’m pretty sure they are chinesium since I don’t recognize the brand.

General rule of thumb to limit capacitor stress/premature degradation is to implement a precharge circuit when power is lost. Otherwise avoid de-energizing or re-energizing the capacitors, which is the main stress point. The electrical surge deforms the inside over time until they short.

Also you can replace capacitors with ones of higher voltage rating as long as the capacitance value is the same, this is a general fix for most circuitry

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Depending on the design, especially if it is higher frequency, capacitor ESR matters too.

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