Empirical modelling of current density distribution as a function of potential, flow velocity, and electrolyte concentration in alkaline water electrolysis

This article gives a critical review of data obtained from previous studies involving the current distribution on the cathode during alkaline water electrolysis. From previous experimental data, empirical models, relating current density distribution on the cathode to potential, electrolyte flow velocity and electrolyte concentration, have been proposed; this approach contributes significantly to understanding the cathode behaviour during alkaline water electrolysis, where the screening caused by gas void distribution along the cathode controls the current distribution locally and globally. For each operating condition, a fourth-degree polynomial model has been observed, fitting experimental data previously. Empirical correlations have been developed over potential, concentration and electrolyte flow velocity ranges. These correlations have been compared with previous data and show good accuracy over the studied ranges.