Importance of overvoltage:

• The existence of overvoltage explains numerous phenomena. Within a lead accumulator, during charging, a metal is deposited on the cathode instead of hydrogen being evolved, because of the high overvoltage of lead.
• It is possible to deposit electrolytically the metals that have a more negative potential than hydrogen like as zinc, cadmium, tin, etc. from an acid solution because of high overvoltage of hydrogen on such metals.
• Overvoltage plays an important role within the organizational production of chlorine and sodium hydroxide through the electrolysis of brine - sodium chloride solution.
• While electrodes of high overvoltage are used in electrolytic reduction, it would mean to raise the reducing power. Electrodes along with high overvoltage like lead alternatively of platinum are used in organic electrolytic reductions to get the desired products.