Difference between ESR and ESI in Electolytic caps

I am trying to understand why the output capacitor in a switching regulator must be low ESR, and how that varies from ESI. Can anyone help?

 

ESR means Equivalant Series Resistance. It is the resistance of the electrolyte and increases the impedance of the capacitor - which is a bad thing.

I have never heard of ESI in connection with electrolytics,

 

What is ESI? Is it Equivalent Series Current?

 

hi

if you want your electro cap to give a long service life use low esr type but it does not mean that you can't use electro caps with a considered high esr.