Evaluation of materials and components degradation of a PEM electrolyzer for marine applications

An investigation of components degradation in a polymer electrolyte membrane (PEM) electrolyzer technology for naval application is carried out. In naval applications, an electrolyzer has to work using treated seawater obtained on board. Electrolyzer performance is evaluated in terms of hydrogen production per unit of electrical energy input starting from a seawater desalination plant simulating the conditions on board of the ship. A desalinator plant, tailored for the specific application, is designed to produce water having a low ionic conductivity (<5 μS) compatible with the PEM stack electrolyzer requirements. Electrochemical characterizations are carried out on an in-house developed 9-cells PEM electrolyzer by using treated water. Several aspects related with the degradation of materials and components electrolyzer are investigated under oxidizing atmosphere. Specific tests are carried out in a corrosive ambient that simulates the sea environment in terms of humidity, salinity, corrosive conditions etc… In order to simulate highly oxidizing atmosphere, a Dry Corrosion Test Cabinet (DCTC®) is used to test MEAs and electrolyzer components on the basis of specific international norms (ASTM standard). Both materials and components are characterized by electrochemical and physico-chemical analysis before and after the DCTC® treatment.