United Chemi-Con PSG with 20,000h endurance!

[mockingbird]

Re: United Chemi-Con PSG with 20,000h endurance!

Those early Fujitsu polymers were inconsistent insofar as reliability. Sometimes they would slightly bloat and go open after a couple years, other times they'd last much longer... quite a few 16+ year old Fujitsu polymers are still good.

Even the crusty ones probably still work ok. It would be interesting to see exactly what effect there is when the polymer dries out some. I'm in the process of constructing my ESR meter so I'll be able to check them in the future.

Regarding the bloating, it was also mentioned at the time IIRC that bloat on bumblebees was harmless and that the top should just be manually pushed back in.

However, so long as that doesn't happen, I would peg polymers as more reliable than even good electrolytics. The reason being that good electrolytics will eventually dry out (or possibly leak) even with a good rubber bung. Electrolytics also rely upon hydrogen scavengers, hydrogen absorbers, depolarizers, neutralizers, oxidizers, and other additives to preclude the generation of hydrogen gas, a process that is always occurring even minimally in all electrolytics. Polymers do not have a liquid solution that is bound to eventually decompose (although they may experience field crystallization over time, decreasing the conductivity of the polymer electrolyte).

What do you reckon then caused the polymer to harden up like that? Plastic shouldn't degrade like that when it's not exposed to UV, right?

As for Sanyo OS-CON, there are two different types of “OS-CON” capacitors: those that use a conductive functional polymer (PEDOT) as the cathode layer material (those unsleeved) and those that use TCNQ complex salt (those with the lilac sleeve, which were discontinued 7 years back). Those have a much lower pyrolysis temperature than polymers, and also rely on temperature multipliers for the ripple rating (unlike polymers). I'm guessing the latter are the ones that age badly.

Yes, correct... They also have an epoxy bunge (as in, the epoxy was filled in to form and stiffen during manufacture).

the degraded poly's i saw where the purple sleeve ones - the blue-sleeve ones seem less degraded with age.
both pulled from the same intel motherboards - so had identical hours on them.

You're referring to the UCC OS-CONs. I have some of those too I should really have a peek inside one of them.

[stj]

Re: United Chemi-Con PSG with 20,000h endurance!

the degraded poly's i saw where the purple sleeve ones - the blue-sleeve ones seem less degraded with age.
both pulled from the same intel motherboards - so had identical hours on them.

[Wester547]

Re: United Chemi-Con PSG with 20,000h endurance!

Yeah, Chemi-con has been rating their polymers for 15,000 hours - 20,000 hours at 105ºC at the rated voltage for a while now. That’s not at the rated ripple current, however, which would increase the core temperature (in the case of polymers since they are rated for very high ripple ratings) an additional 20ºC (105ºC polymers have a maximum core temperature of 125ºC), thus decreasing the lifespan to 1,500 - 2,000 hours.

Nichicon confirms this much, if you use Nichicon’s online capacitor calculator and put in the maximum rated ripple current in both ripple current fields, then calculate the results. In accordance to this document by Chemi-con, the formula for calculating life expectancy for polymers is different to that of electrolytics (pages 11 and 12). A polymer’s lifespan will increase 10x per 20ºC drop (although polymers that are sealed with rubber are still only rated for 15 years max, in accordance to that calculator and Chemi-con).

Out of curiosity, I opened up two polymers last night. The first, a Sanyo OSCON, probably around 15 or so years old. The second, a Fujitsu bumblebee.

These are both polymer caps. People have speculated that the bumblebees were "hybrid polymer", but I'm not sure what they meant by it, because it looked like an ordinary polymer to me.

Now the surprising part was that BOTH the polymer caps had dry, crusty insulative polymer layers.

Yep, willawake dissected a bumblebee Fujitsu polymer many years ago and found the same thing.

Rubycon’s PZA series also has a vent stamp, but there is no mention on their site of PZA being a “hybrid” in any sense of the word. PCBONEZ was somehow (may still be somehow) convinced that the older Fujitsu polymers are hybrids because they are “functional” polymers, but looking at page 3 of that Chemi-con document, “functional polymer” is just another term for solid polymer. Hybrids do exist, of course, but their specs are not as good as regular polymers.

Those early Fujitsu polymers were inconsistent insofar as reliability. Sometimes they would slightly bloat and go open after a couple years, other times they’d last much longer... quite a few 16+ year old Fujitsu polymers are still good.

It got me thinking: Was this just a result of early polymer technology, or will modern polymers also degrade to this degree over time. Seeing your thread title gets me thinking again whether polymers are indeed better than good electrolytics over a long period of time.

The 20,000 hour load multiple (the rule that longevity increases with lower stress), may not apply to polymer capacitors. Yes, they may be able to withstand a harsh environment in the longer run versus an electrolytic cap, but they probably can't compete with an electrolytic cap in the long run under low-stress conditions.

The one advantage liquid electrolytics have over polymers is a genuine self-healing mechanism: so long as the pH balance of the electrolyte hasn’t risen and the electrolyte hasn’t dried up, they are very capable of correcting any defects or issues in the anodic oxide layer, as long as there is bias applied to the plates. Polymers are capable of isolating faults but not correcting them. So it’s possible for a polymer to fail by way of a random short-circuit after many years, especially since leakage current goes up.

However, so long as that doesn’t happen, I would peg polymers as more reliable than even good electrolytics. The reason being that good electrolytics will eventually dry out (or possibly leak) even with a good rubber bung. Electrolytics also rely upon hydrogen scavengers, hydrogen absorbers, depolarizers, neutralizers, oxidizers, and other additives to preclude the generation of hydrogen gas, a process that is always occurring even minimally in all electrolytics. Polymers do not have a liquid solution that is bound to eventually decompose (although they may experience field crystallization over time, decreasing the conductivity of the polymer electrolyte).

As for Sanyo OS-CON, there are two different types of “OS-CON” capacitors: those that use a conductive functional polymer (PEDOT) as the cathode layer material (those unsleeved) and those that use TCNQ complex salt (those with the lilac sleeve, which were discontinued 7 years back). Those have a much lower pyrolysis temperature than polymers, and also rely on temperature multipliers for the ripple rating (unlike polymers). I’m guessing the latter are the ones that age badly.

[stj]

Re: United Chemi-Con PSG with 20,000h endurance!

oscon's do age badly.
i cant say if anything else does because i have only seen really old oscon's

[mockingbird]

Re: United Chemi-Con PSG with 20,000h endurance!

Out of curiosity, I opened up two polymers last night. The first, a Sanyo OSCON, probably around 15 or so years old. The second, a Fujitsu bumblebee.

These are both polymer caps. People have speculated that the bumblebees were "hybrid polymer", but I'm not sure what they meant by it, because it looked like an ordinary polymer to me.

Now the surprising part was that BOTH the polymer caps had dry, crusty insulative polymer layers.

It got me thinking: Was this just a result of early polymer technology, or will modern polymers also degrade to this degree over time. Seeing your thread title gets me thinking again whether polymers are indeed better than good electrolytics over a long period of time.

The 20,000 hour load multiple (the rule that longevity increases with lower stress), may not apply to polymer capacitors. Yes, they may be able to withstand a harsh environment in the longer run versus an electrolytic cap, but they probably can't compete with an electrolytic cap in the long run under low-stress conditions.

[PeteS in CA]

Re: United Chemi-Con PSG with 20 000h endurance!

You're a Mouser Browser?

More seriously, back when I was looking at polymers for Curtis Inst. they were usually rated for 2000 hours. They've come a long way!

[Per Hansson]

Was browsing Mouser looking to get some new 1500uF 10v caps in 10x16mm size to replace UCC KZG and Nichicon HM rated at 0.018Ω ESR and 2000mA ripple.
No such caps in electrolytic versions really exist from reputable brands anymore.

So I looked at the solid polymer range and came across the updated version of the UCC PSG.
It's rated for 0.008Ω ESR and 7700mA ripple with an endurance of 20000h, that is 10 times the endurance of the KZG & HM electrolytics!
Have not seen anything like that before!
I have been using Sanyo SEPC 820uF 4v solid polymers in place, they are rated for 0.007Ω ESR and 6640mA ripple, but "just" 5000h endurance.
Might actually get the 1000uF version of the UCC PSG next time I order, as it's ESR is slightly higher at 0.012Ω putting it closer to the originals

If Z height is no objection then the electrolytic Panasonic FR 1500uF 16v at 10x20mm with 0.020Ω ESR and 2180mA ripple is a given choice.
Being rated at 10000h it's a pretty much identical replacement.
But as can be seen in the picture that can not always be used everywhere