When current starts flowing in a circuit, voltage of the battery drops from EMF value. There are three sources of this however here I am only interested in ohmic resistance of the battery.
EMF of the battery is created because of electrochemical processes on both electrodes which create potential difference on electrode/electrolyte interface due to charge separation.
When talking about ohmic resistance of the battery I am not sure how does ohmic resistance of battery components affect charge separation on the interface. What does ohmic resistance of electrolyte or electrodes have to do with equilibrium of electrochemical reactions on the electrodes?