HSTE stack under pressure with maximum contact area and gas distribution through the electrode – APHRODITE

The Aphrodite Project deals with hydrogen production by High Temperature Steam Electrolysis (HTSE). It aims at designing, manufacturing and testing a new concept of HTSE stack with high performances by operating at high pressure (30 bar). It is not only an innovative design but also a new approach for stacking the different elements, for sealing and for using gas pressure. To our best knowledge, this concept has no equivalent, and is the first HTSE planar stack under pressure. This industrial research project focuses on HTSE testing under pressure associated with modelling the thermal, electrochemical and mechanical response of the stack. For this, a study of electrochemical phenomena involved in high pressure for each electrode will be conducted as part of a thesis. Moreover, these models will be introduced in a simulation tool to analyze and size further tests. The software platform from the MOISE project (ANR 2007) will be used and expanded. A step by step experimental validation (Gas and current leads, tightness, integrity of cells during assembly ...) will be conducted prior to pressure testing in order to optimize the stack design. Seals will be metallic and innovative, coming from the project EMAIL (ANR 2007). The pressure tests conducted at different scales (cell, single repeat unit and stack) will allow the understanding of phenomena involved in the HTSE under high pressure. These tests will also supply a validation of this process for massive hydrogen production.
The general approach for the project organization is to conduct in parallel:
- Action to enrich the knowledge of the HTSE under pressure;
- manufacturing and testing of a first HTSE stack under pressure, based on an innovative concept devoted to a running under pressure.
- Quantification thanks to simulations of the performance gains (optimization of the surface, water use rate, performance of production, degradation ...) really obtained in the concept.