Something new to me is that when you put 2 (or more) supercaps in series that one of them could reach a higher voltage than the other and possibly exceed its rated voltage.
It appears there are 2 mechanisms by which this happens, one is variance in capacitance and the other is variance in leakage current.
I've been searching the internets for hours and all I ever see is they talk a little bit about it and jump right into how to balance the supercapacitors.
What I would like to know is the long-term effect. For example does the leakage continue to increase voltage to one or does it reach an equilibrium.
Let's say I had a battery with 4V exact and would stay like that forever and I connect 2 super caps in series rated at 2.7V each. Let's say I let this experiment go for a whole year. Would the imbalance continue to build up until one of the capacitors fails? Or will the imbalance reach some type of equilibrium where it settles and with an extra 1.4V margin across both capacitors maybe it would ultimately settle still within the rated voltage.
I'll also report back if I find out more, and I'll be doing some experimentation as well.
It appears there are 2 mechanisms by which this happens, one is variance in capacitance and the other is variance in leakage current.
I've been searching the internets for hours and all I ever see is they talk a little bit about it and jump right into how to balance the supercapacitors.
What I would like to know is the long-term effect. For example does the leakage continue to increase voltage to one or does it reach an equilibrium.
Let's say I had a battery with 4V exact and would stay like that forever and I connect 2 super caps in series rated at 2.7V each. Let's say I let this experiment go for a whole year. Would the imbalance continue to build up until one of the capacitors fails? Or will the imbalance reach some type of equilibrium where it settles and with an extra 1.4V margin across both capacitors maybe it would ultimately settle still within the rated voltage.
I'll also report back if I find out more, and I'll be doing some experimentation as well.