I obtained some supercaps from an auction site.
As is often the case for low cost components from such sources, these do not have supplied data and such branding as there is does not appear traceable.
I would like to know if there is a standard for polarity for such devices and how likely it is that generic devices such as this one follow the "standard".
My samples have an arrow on the label which may indicate polarity, but this is uncertain.
To make my query specific, but also liable to be generally useful, here is a set of closely related questions:
What is the polarity of this supercapacitor (4F, 5.5V)?
How was the polarity determined in this case?
Is there a standard for polarity for such capacitors?
What does the arrow indicates?
Some details of specific product here
Including this diagram: