In concept, an analytical approach to the design and characterization of an electrochemical reactor might consider a complete treatment of the following aspects:
1. Mass balance (including the electrical charge balance) for all reactants and products.
2. Heat balance across all reactor compartments and components.
3. Voltage balance across the reactor.
The electrodes and the separator are the only components in an electrolytic cell which are not to be found in other chemical reactors. The detailed design and characterization of such reactors may involve complex, interactive procedures and understanding of factors such as potential and current distribution, electrolyte flow patterns, electrode thermodynamics and kinetics, mass and heat transfer besides the cost and the reactor components. These factors are common to all chemical engineering processes with the important exception of potential distribution.