In electrochemistry, all electrode potentials are quoted with reference to the standard hydrogen electrode. Its value is assigned to be 0 volts. I have been searching for the origin of this convention (it is nearly impossible to determine its absolute potential). I searched for a while using Google Scholar/ Google books from the 19th century, but it is quite elusive. Cant't find the inventor of the hydrogen electrode nor the origin of the convention of assigning zero volts to its half cell. The context is given below:
The Standard hydrogen electrode (abbreviated SHE), is a redox electrode which forms the basis of the thermodynamic scale of oxidation-reduction potentials. Its absolute electrode potential is estimated to be 4.44 ± 0.02 V at 25 °C, but to form a basis for comparison with all other electrode reactions, hydrogen's standard electrode potential (E0) is declared to be zero volts only at 298K. Potentials of any other electrodes are compared with that of the standard hydrogen electrode at the same temperature.