The Electrochemistry Module covers a wide range of applications involving electrochemical reactions. This is accomplished through interfaces for primary, secondary, and tertiary current distributions; electroanalysis; flow in free and porous media; heat transfer; heterogeneous and homogeneous chemical reactions; and material transport in dilute and concentrated solutions. Possible applications include the study and design of chlor-alkali and chlorate electrolysis, water electrolysis for hydrogen and oxygen production, waste water treatment, desalination of seawater, fundamental electrochemical studies in electrocatalysis and electroanalysis, and sensors for glucose, pH, hydrogen, and other gases.

Analysis of electrochemical systems is central to electrodeposition, corrosion, battery design, fuel cells, and electrolysers. Because of this, all of the functionality available in the Electrochemistry Module is also included in the following products: Electrodeposition Module, Corrosion Module, Battery Design Module, and Fuel Cell & Electrolyser Module.

Interfaces embedded in the Electrochemistry Module enable the modelling of systems assuming primary, secondary, or tertiary current distributions. The primary current distribution utilises Ohm's Law together with a charge balance to model the flow of current in both the electrolyte and electrodes, while assuming that losses in electric potential due to the electrochemical reactions are negligible. The secondary current distribution includes these reaction-based losses and is modelled through interfaces for the Tafel and Butler-Volmer equations. These also support modifications and custom expressions. The interfaces include electric potential as part of the electrochemical reaction kinetics.

In many reacting systems, and in close proximity to the electrodes, the concentration of the electrolyte is not constant. In that case, the effects of diffusion and convection have to be considered in addition to migration. The Electrochemistry Module provides an interface for tertiary current distributions that utilises the Nernst-Planck equation to describe the transport of chemical species in the electrolyte. Utilising the unparalleled capabilities in COMSOL Multiphysics, this interface can be seamlessly coupled to other interfaces that describe fluid flow and heat transfer.