Modeling and simulation of an electrolyser for the production of HHO in Matlab- Simulink®

The electrolyzers work through an electrochemical process, their derivatives (H2,O2 , and HHO) are used as enriching fuels due to the electrolysis of water, being cleaner than gasoline and diesel. This article presents the dynamic model of an alkaline electrolyzer that uses an electrolyte ( KOH o NaHCO3) dissolved in distilled water to accelerate the production of oxyhydrogen (HHO). The model shows the phase change that occurs inside the electrolytic cell. The EES® software was used to determine the values ​​of enthalpy, entropy, and free energy that vary during the electrochemical reaction; the equations were simulated in Matlab-Simulink® to observe their dynamic behavior. The Simulations presented varying every 5 g the electrolyte until reaching 20 g. The flow rate of HHO with potassium hydroxide (20 g) is higher than 0.02 L / s, and with sodium bicarbonate (20 g) it is above 0.0006 L / s, confirming what the literature of alkaline cells state, that the most efficient electrolyte for its energy conversion is KOH.

The Electrode-Electrolyte Interface in Acidic and Alkaline Fuel Cells

This numerical study presents the role of diffuse region of the electric double layer in both acidic and alkaline fuel cells. The numerical model is based on the Poisson-Nernst-Planck (PNP) and generalized-Frumkin-Butler-Volmer (gFBV) equations. The Laminar Flow Fuel Cell (LFFC) is used as the model fuel cell architecture to allow for the appropriate and equivalent comparison of acidic and alkaline cells. In particular, we focus on how each device behaves to changing reactant supply at the electrodes, including the overall cell performance and individual electrode polarizations. It is found that the working ion concentration at the reaction plane contributes to differing performance behaviors in acidic and alkaline fuel cells, including activation losses and reactant transport overpotentials. This is due to the working ion, and the electrode where it’s consumed, being opposite for acidic and alkaline fuel cells.