Anion exchange membrane electrolysers

Overview of the status and impact of the innovation



AEM electrolysers are based on the same chemical reaction as ALK electrolysers and use the same materials. The differences are that AEM electrolysers use a polymer membrane, which allows anions but not photons to cross, and they have a simpler, more compact design. Thus, AEM electrolysers do not require noble catalysts or titanium (like PEM electrolysers) and can be used in smaller-scale projects than ALK electrolysers. This makes AEM electrolysers the only modular variety. Nevertheless, further innovation is needed to overcome the primary issues with AEM electrolysers, such as the fact that complex and unstable polymer chemistry, performance inefficiencies and instabilities that can shorten lifetimes. Improvements are also required to increase their power range. The technology is still at an early stage, so current costs are unknown.


AEM electrolysers combine the less harsh conditions of ALK electrolysers (and the resulting lack of requirement for expensive materials) with the simplicity and efficiency of a PEM electrolyser. As a result, they have a considerable potential cost advantage over PEM electrolysers, while also offering a high degree of flexibility and short response times, thus enabling greater integration of renewable generation sources.