Tubulyze- Development of a tubular water electrolyzer

Summary

Due to the constantly growing demand for energy and the scarcity of fossil resources, the necessity of clean and sustainable energy production and storage is becoming increasingly important. One solution is the generation of H₂ and O₂ by water electrolysis. H₂ can be used in fuel cells for energy generation, but also as raw material for the chemical industry.

Water electrolysis is carried out industrially in two different processes: alkaline or acidic electrolysis. The acidic electrolysis has many advantages over the alkaline: reduced gas cross-over of the membrane, higher conversion efficiency, fewer corrosion issues and compact design. Furthermore, the operation over a wider range of current densities is possible. However, the need for precious metals for electrode manufacture and the high cost of the membrane make it necessary to optimize the system. This is where the joint project Tubulyze comes in.

The aim of the project is to develop a tubular PEM (Proton Exchange Membrane) water electrolysis cell with novel processes to reduce material costs (precious metal loading ≤ 50 µg cm^-2) without reducing energy efficiency (≥ 70% at ≥ 15 mA cm^-2). The electrochemical characterization of the tubular cell and its components is the focus of the electrochemistry group. Planar cells will be investigated as reference system and the tubular electrodes will be characterized and its long-term stability will be examined.

Figure 1: Schematic representation of a tubular water electrolysis cell with the three most important innovations of the Tubulyze project and the project partners