Electrode potential is the potential difference developed between an electrode and electrolyte. It is the measure of the tendency of an electrode to lose or gain electrons when it is in contact with a solution of its own ions. The standard electrode potential is the electrode potential of a half-cell under standard conditions, which is defined as a temperature of 298K, pressure of 1 atm, and concentration of 1M. It is measured with the help of a reference electrode known as the standard hydrogen electrode (SHE), whose electrode potential is 0 volts. The standard electrode potential of an electrode can be measured by pairing it with the SHE and measuring the cell potential of the resulting galvanic cell. The symbol ‘Eocell’ represents the standard electrode potential of a cell.

The cell potential is the potential difference between the two electrodes of a galvanic cell. It is the measure of the driving force of the reaction and is calculated by subtracting the potential of the anode from the potential of the cathode. The cell potential is positive if the reaction is spontaneous and negative if it is non-spontaneous.

In summary, electrode potential is the potential difference between an electrode and electrolyte, while standard electrode potential is the electrode potential of a half-cell under standard conditions. The cell potential is the potential difference between the two electrodes of a galvanic cell.