In the direction of current flow the potential drop across the resistor. The positive terminal of the battery is higher than the negative terminal of the battery by a potential difference equal to the e.m.f. Combining these two effects the resultant p.d across the battery with internal resistance and current flowing through it is (E - ir) . This is equal to external p.d V (= iR). If no current flow through a battery with internal resistance r the terminal p.d remains E.
