Performance Analysis of Alkaline Water Electrolysis System Based on Heat Current Modeling Method

With the rapid promotion of hydrogen energy, hydrogen production technology becomes a key area of future energy research. Herein, alkaline water electrolysis (AWE) is a mainstream technology, and the study and optimization of its performance are of great significance. However, in the process of coupling electric hydrogen production and power electronic devices, different subsystems have different mathematical properties, which is difficult to construct models together. And the strong coupling between electricity and heat affects the overall analysis of AWE systems. In order to establish an isomorphic model with the circuit network, a cross-scale heat current model of AWE system is established to describe heat transfer and electrochemical processes following a unified equivalent circuit form. The influence of parameters such as temperature and pressure on the system performance and internal characteristics is investigated. As the cooling water flow rate increases from 0.3 to 0.7kg/s, the cell voltage rises by 0.1 V, and voltage efficiency decreases by 2.7%. Comparing the current-voltage polarization curve with single-cell experimental data conducted by HRI, the maximum relative errors is less than 0.5%, comparing the system result with Aspen simulation, the maximum relative errors is less than 0.43% and 0.1%, validating the effectiveness of the proposed model.