The electrolytic water hydrogen production system is composed of an electrolytic cell and an auxiliary system, in which the electrolytic cell is the main place where the electrolytic reaction occurs, and the auxiliary system includes power conversion, water cycle, gas separation, gas purification and other modules.

According to the nature of electrolytic water can be divided into ALK (alkaline electrolysis), PEM (proton exchange membrane electrolysis), AEM (anionic electrolysis) and SOEC (solid oxide electrolysis).