New membrane materials for PEM water electrolysis
In the MaPEI project researchers of Forschungszentrum Jülich combined
advantages of alkaline and PEM electrolysis by using anion exchange
membranes. Jointly with FuMA-Tech they developed novel high-performance membrane electrode assemblies (MEAs) for alkaline PEM electrolysis.
|Project status||Project completed|
|Project duration||July 2012 until June 2015|
If water electrolysis technology, and in particular PEM electrolysis, are to be widely and sustainably used on the mass market for the storage of renewable energies after 2020, further steps must be taken to solve outstanding technical issues, such as improving low power densities and inadequate stability, as well as reducing the high costs associated with the technologies currently in use.
The main challenges here are improving the chemical stability of existing membranes at higher temperatures, increasing the conductivity, and integrating the ionomer into the catalyst layers so that the alkali ions will no longer be needed in the electrolysis cycle. Another approach aims to develop membranes that are stable in alkaline solutions, and to use them to improve partial load toleration in conventional alkaline electrolysis and to increase the current densities.
The project can be broken down into three phases:
- membrane development and characterization
- development of membrane electrode assemblies (MEAs)
- testing of suitable MEAs in electrolysis operation.
Noble metals become dispensable
The use of anion exchange membranes avoids the application of noble metals like platinum and iridium, which are normally used in conventional PEM electrolysis because of high corrosiveness.
As the cost of noble metals together with the cost of separator plates and current collectors make up a significant proportion of the stack costs of a PEM electrolysis stack, the use of non-noble metals in the catalyst layer will reduce the investment costs associated with an electrolysis plant.
Membrane development: In this sub-project, membranes that are stable in alkaline solutions and anion exchange membranes will be developed that are characterized by a high alkaline stability at high temperatures and pressures as well as a low surface resistance and low gas crossover.
MEA development: In this sub-project, these novel membranes will be used to develop and fabricate membrane electrode assemblies (MEAs) that are characterized by higher performance data and an expanded partial load range compared to conventional alkaline electrolysis.