Yes, as the size of the capacitor shrinks, the plates get closer and it becomes harder for the dielectric to maintain charge (hence voltage) without arcing. Bt

Yes, as the size of the capacitor shrinks, the plates get closer and it becomes harder for the dielectric to maintain charge (hence voltage) without arcing. Btw they are talking about supercapacitors which are a specific kind of capacitor that is more like a battery: https://en.m.wikipedia.org/wiki/Supercapacitor https://en.m.wikipedia.org/wiki/Supercapacitor