New Anion Exchange Membrane Electrolysers

The potential proposal should:

• Develop and redefine new components for AEM electrolysers, including membrane, ionomers, PGM-free electrode packages, porous interconnectors and separators;
• Implement the newly developed components in a 1 kW stack with a minimum of 5 cells;
• Achieve current PEM electrolysis performances as defined by the MAWP, with diluted circulation of electrolytes but gradually move to pure DI water circulation (< 20 μS cm-1), reaching single-cell voltages of 2 V at 1 A cm-2 at 45°C and maintain stable performance at constant current for 2,000 h with a degradation gap of less than 50 mV;
• Make a clear correlation between the developed materials/components and the achieved cell performance and durability;
• Provide cost assessment for the developed technology and scale-up. The technology should clearly demonstrate component cost reduction compared to current PEM electrolysis technology.

It is expected that the consortium include industrial companies capable of scaling up and commercializing the technology developed. The focus of the project should be clear on the combination between materials research and performance testing.

It is expected that the project will contribute towards the objectives and activities of the Hydrogen Innovation Challenge (as detailed under section 3.2.G. International cooperation). Promoting international collaboration beyond EU Member States and H2020 Associated Countries is therefore strongly encouraged.

The technology should start at TRL 2 and reach TRL 4 at the end of the project.
Any safety-related event that may occur during execution of the project shall be reported to the European Commission's Joint Research Centre (JRC) dedicated mailbox JRC-PTT-H2SAFETY@ec.europa.eu, which manages the European hydrogen safety reference database, HIAD and the Hydrogen Event and Lessons LEarNed database, HELLEN.

Test activities should collaborate and use the protocols developed by the JRC Harmonisation Roadmap (see section 3.2.B ""Collaboration with JRC – Rolling Plan 2019""), in order to benchmark performance of components and allow for comparison across different projects.

The FCH 2 JU considers that proposals requesting a contribution of EUR 2 million would allow the specific challenges to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.

Expected duration: 3 years.

Hydrogen is an important raw material for chemical syntheses (ammonia, methanol etc.), metallurgical reduction reactions and oil refining. Nowadays, it is mostly generated by reforming hydrocarbons, which is associated with a significant carbon footprint.

Proton exchange membrane (PEM) electrolysis has evolved into a mature technology with promising perspectives to play a key role for production of green hydrogen in the future energy landscape. However, the use of PEM electrolysers for producing a meaningful percentage of the annual hydrogen production rate in Europe would require the installations at gigawatt scale. The electrodes of state-of-the-art PEM electrolysers require a significant loading of platinum-group metals (PGMs), particularly iridium. Hence, such a large-scale deployment of PEM electrolysers raises major concerns about the availability and price of these raw materials. On the other hand, the electrodes of alkaline water electrolysers do not require PGMs. However, at present alkaline electrolysers operate at low current densities due to the high resistance of the relatively thick separators.

Anion exchange membrane (AEM) electrolysis can potentially combine the beneficial features of the PEM and alkaline electrolyser technologies, i.e. a low cost, raw materials that do not raise concerns in terms of supply bottlenecks (electrodes that do not include PGMs, stainless steel current collectors), a compact design, the adoption of feeds based on non-corrosive liquids (low concentration alkali or DI water), and differential pressure operation. However, as of today AEM electrolysis is limited by AEMs exhibiting an insufficient ionic conductivity as well as a poor chemical and thermal stability. Moreover, most non-PGM electrocatalysts, in addition to poor electrical conductivity mentioned, are only stable above pH 12, and really active at pH 14. Therefore, new material breakthroughs and design concepts are needed before AEM technology can challenge PEM electrolysers. These include:

• Increase in membrane and ionomer conductivity and stability;
• Decrease in membrane thickness while retaining good gas separation;
• Improve mechanical stability;
• Optimize chemical composition and activity of non-PGM electrocatalysts;
• Optimize electrocatalyst conductivity, dispersion and utilization in the electrode;
• Improved cell design.

The AEM electrolyser short stack including the newly developed components will offer a promising and cost-effective alternative to PEM electrolysis technology paving the way for larger systems. The expected impacts are:

• Stable and cost-effective components for AEM water electrolysers that will reduce substantially the risk to incur in supply bottlenecks, the investment costs and thus the total €/kg H2;
• New knowledge with respect to the design and operation of an AEM electrolyser stack including the new components;
• Understanding of the correlation between degradation processes in materials and the operation conditions such as temperature and current density;
• Increased EU competitiveness in production of green hydrogen from renewable sources at large scale.

The expected KPI to be achieved by AEMs are:
1) Area specific resistance (ASR): ≤ 0.07 Ω cm2 (room temperature);
2) OH- conductivity of membrane: 50 mS cm-1 (room temperature);
3) Swelling ratio (dry/wet): [dimensional stability]

• Machine Direction (MD): ≤ 1 %;
• Transverse Direction (TD): ≤ 4 %;

4) Mechanical strength: 15 MPa; elongation at break: 100 %;
5) Ionomer conductivity: 20 mS cm-1
6) Stability: 2,000 h, ASR remains.

Type of action: Research and Innovation Action

The conditions related to this topic are provided in the chapter 3.3 and in the General Annexes to the Horizon 2020 Work Programme 2018– 2020 which apply mutatis mutandis.