Cell voltage is usually applied to a battery type electrochemical system where the voltage is simply the electrical energy difference between the cathode and the anode of the cell. Electrode potential is more commonly used to describe an electrode in an experimental electrochemical system and describes the energy difference between one electrode and some reference energy, often this is a reference electrode of some kind, e.g. a silver / silver chloride reference electrode. Reference electrodes exhibit stable electrochemical energy (voltage) under a wide range of conditions.