Project News

Achieving Milestones in CO2 Electrolysis: MS9 and MS10

In the progressive world of CO2 Electrolysis, milestones MS9 and MS10 mark significant advancements, albeit with unique challenges. The recent achievement in MS9 was notable, as the cell potential reached an impressive 300mA/cm2 at 2V per cell. This indicates a substantial improvement in efficiency and performance, albeit not fully meeting the set milestone.

Achieving Milestones in CO2 Electrolysis: MS9 and MS10

Turning to MS10, significant strides were made in material selection. The milestone involved the critical selection and freezing of Gas Diffusion Layers (GDLs) and catalysts for both anode and cathode sides. This decision is crucial as it lays the foundation for the future efficiency and reliability of the fuel cells.

However, these advancements didn’t come without their challenges. One of the primary issues encountered was the stability of the test in terms of operational hours. This was primarily due to the clogging of the flow field, a result of salt precipitation. This phenomenon poses a significant threat to the consistent operation and longevity of the fuel cells.

In response to these challenges, researchers and engineers are diligently studying new procedures to mitigate these issues. Developing strategies to avoid clogging and ensure uninterrupted operation is a top priority. Another obstacle that surfaced was related to the scaling up of the substrate and the supplying materials. This highlights the complexities involved in transitioning from laboratory-scale successes to large-scale, commercially viable solutions.

Despite these challenges, the progress made in milestones MS9 and MS10 is a testament to the ongoing innovation in CO2 Electrolysis. As solutions to these challenges are developed, we can expect further advancements in this promising field, paving the way for more sustainable and efficient energy solutions.

Source: CNR & DeNora

Project News

Progress on the anion exchange membrane

Hydrolite has continuously improved its anion exchange membrane, reaching several important milestones. Ethanol crossover has been reduced by an order of magnitude, from 12 mA/cm2 to 0.3 mA/cm2 (70 °C, 0.5 M in 1 M OH) as shown in Figure 1.

As ethanol is one of the desired products from the CO2 electrolysis, it is crucial to prevent from crossing over the membrane.

Figure 1: Ethanol crossover versus temperature for older generation (left) and newer generation (right) membranes produced at Hydrolite.

Using a setup specially developed at DTU, CO2 crossover could be measured for various membranes. It is now understood that CO2 crossover increases significantly with increasing current, meaning the CO2 is mainly driven by ionic current crossing the membrane from the cathode to the anode. It was shown the Hydrolite membrane displays lower crossover of CO2 than a commercially available membrane as showed in Figure 2.

It is important to mention that those improvements were achieved without compromising the hydroxide conductivity of the membrane (> 150  mS/cm at 60 C, in-plane, 100 %RH). One remaining challenge is reaching the mechanical tensile strength target of 20 MPa at 60 °C. Recent developments have shown an improvement of the tensile strength of Hydrolite membranes from 4 to 17 MPa, hence approaching the target. We are confident that this milestone will be reached soon.

On the fabrication side, Hydrolite delivered to its partners about 10 m2 of large size membrane for the CO2 electrolyser prototype. Significant efforts are being invested to further scale up the membrane fabrication for the supply of 100 m2 of high quality membranes for the demonstrator stack in early 2025.

Figure 2: Hydrolite membrane (bottom) showing improved CO2 barrier as compared to commercial membrane (top)