Identify the part - what is it?

[spec]

Perhaps you may not be aware but on this side of the pond the term "Super" is often used to denote "big quantity" which may not make a whole lot of sense to our friends in UK ( hey, I have British relatives)----but sorry I did not start the term

... they are really exceptionally unreliable-

I'd have to disagree with that sentence;
Granted it may be unreliable in Consumer Electronics which is mostly based on design issue and not critical. (Although countless number of them were used throughout the product cycle).
When designed properly, lifetime hours are not that far from the respective datasheets. There are many factors involved with several reports by likes of Yamaha, Panasonic ELNA and Mitsumi
Speaking of reliability, in Aviation, Airbus 380 has been using super capacitors for some time (Emergency evacuation sliders). Wonder how reliable is that

We do speak US in the UK too.

My opinion, for what it is worth, is that you are both right.

When super capacitors first came out they were fussy, unreliable things that needed to be treated with kid gloves, and some versions were better than others. But, the technology has matured and you can get reliable supercaps now, but you obviously need to take note of the data sheet- the net is full of dubious circuits using supercaps. This also applies to LiIon batteries.

Just like LiIon batteries, if you stick with good makes you will have fewer problems.

spec

 

[dr pepper]

The ones I pictured were pulled from professional it gear such as a Hp server, so I would have thought quality will be good.
I'v seen others that look like a rechargeable battery, I wonder if those are what Nige has issues with.

 

[Nigel Goodwin]

The ones I pictured were pulled from professional it gear such as a Hp server, so I would have thought quality will be good.
I'v seen others that look like a rechargeable battery, I wonder if those are what Nige has issues with.

I've seen various shapes of them, but never the specific one in this thread.

As for those used in HP servers, what do the specifications for them claim?.

 

[dr pepper]

Couldnt be bothered to look them up, but my experience of pulling apart Hp gear has been the components they use and construction methods are good quality.