Dipped in
the solution, the electrodes exchange charges with the electrolyte The positive electrode has a potential difference V+ (V+ > 0) between
itself and the electrolyte solution immediately adjacent to it marked
A in the figure Similarly, the negative electrode develops a negative
potential  – (V– ) (V– ≥  0) relative to the electrolyte adjacent to it,
marked as B in the figure When there is no current, the electrolyte
has the same potential throughout, so that the potential difference
between P and N is V+ – (–V–) = V+ + V–