**Capacity matters less than max voltage does**

As a former electronics hobbyist and electronic component collector, I can say from experience that much smaller capacitors can be quite dangerous, because they are suitable for high voltages. Even with normal consumer elco capacitors, like the the ones used in back in the 60's for TV power supplies. Capacity of these elco's ranged from 100 micro Farad to say, 0.01F for the really big ones, voltage max e.g. 400V. Triodes and Pentodes were involved, that's why they were made for this voltage range. These capacitors could become quite dangerous to handle, when loaded up with the TV's power supply. 

**Supercapacitors work with low voltages**

In a *supercapacitor*, which could be 100-200 Farads, you could store lots of  Coulombs charge. But generally, the max load voltage of these components is very small, yielding much lower energy content. High voltages cannot be used, because that would pierce the dielectric surfaces in a supercapacitor. It would be huge size.. or special technology.

I can refer to another answer. For supercapacitors, most common is 2.7 Volts.

https://electronics.stackexchange.com/questions/365768/why-arent-there-any-400v-ultracapacitors

Supercapacitors allowing for higher voltages are very rare and expensive. I found below one, it is 130F and it can handle 62.5V. A voltage like that would certainly be felt on the skin, but it will not kill you. And look at the price of this baby..

https://nl.rs-online.com/web/p/electric-double-layer-capacitors/1797440/

If higher voltages would be allowed, supercapacitors would replace batteries immediately ! They are much more durable than batteries, a capacitor can be charged quickly, millions of times. For backgrounds,

https://www.tecategroup.com/products/ultracapacitors/ultracapacitor-FAQ.php