how electrode concentration cell work

Electrode concentration cells:

Two similar electrode at different conc. are dipped in same solution e.g. two hydrogen electrodes at unequal pressure are immersed in same solution of hydrogen ions.In these cells,

The potential difference is developed between two like electrodes at different concentrations dipped in the same solution of the electrolyte.

For example, two hydrogen electrodes at different has pressure in the same solution of hydrogen ions constitute a cell of this type.

(Pt,H2(Pressure p1))/Anode |H+| (H2(Pressure p2)Pt)/Cathode

Pt; H2(p1) | H+ions solution | H2(p2); Pt