AionFLX™ anion-exchange membranes
PFAS-free anion-exchange membranes for AEM water electrolysis and adjacent alkaline electrochemical cells, designed to be qualified together with matching ionomer and CRM-free electrodes.
what it is
AionFLX™ is CENmat’s membrane family for anion-exchange membrane (AEM) water electrolysis. AionFLX™ is PFAS-free, so electrolyser developers can move away from PFAS-based materials without switching to a different cell concept.
The membranes are validated for wet assembly and are supplied in pilot-relevant sheet sizes for qualification and scale-up. They are developed as one system with AionFLX™ ionomer and CENmat’s OXYGN and H2GN electrodes, which shortens the matching work between membrane, catalyst layer and binder.
AionFLX™ is built for long life. The composite version, AionFLX™ Plus, has run for more than 8,000 h in 1 M KOH with a degradation rate below 15 µV/h. The standard AionFLX™ membrane has run for more than 4,000 h in 0.1 M KOH with a degradation rate below 30 µV/h in a separate long-term test (both at 50 °C). Key membrane properties – 1.1 meq/g ion-exchange capacity, 82.7 mS/cm OH⁻ conductivity and a swelling ratio of about 30 % – are in the specification table below.
The membrane chemistry is the same one CENmat scales up in the EU-funded HYScale project, where CENmat is the coordinator.
Applications
- AEM water electrolysis cells and stacks
- Low-concentration alkaline electrolyte operation
- PFAS-free membrane qualification for new stack designs
- Adjacent alkaline electrochemical cells (R&D)
Formats and supply
- Sheets in pilot-relevant sizes for cells and short stacks
- Wet assembly (validated)
- Materials pack with AionFLX™ ionomer and OXYGN/H2GN coated electrodes
key specifications
AionFLX™ Plus composite membrane
> 8,000 h*
continuous operation in a long-term test
< 15 µV/h*
degradation rate
* 50 °C, 1 M KOH
AionFLX™ membrane
> 4,000 h*
continuous operation in a long-term test
< 30 µV/h*
degradation rate
* 50 °C, 0.1 M KOH
| Parameter | Value | Conditions |
|---|---|---|
| Material | PFAS-free; membrane and ionomer from the same material family | |
| Nominal thickness | ≈ 80 µm (dry) | |
| Sheet size | Validated up to 900 cm² | |
| Cell performance | 2.01 V at 2 A/cm²* | * 50 °C, 0.1 M KOH |
| Long-term test, AionFLX™ Plus composite membrane | > 8,000 h at < 15 µV/h* | * 50 °C, 1 M KOH |
| Long-term test, AionFLX™ membrane | > 4,000 h at < 30 µV/h* | * 50 °C, 0.1 M KOH |
| Assembly | Wet assembly (validated) | |
| Ion-exchange capacity (IEC) | 1.1 meq/g | |
| OH⁻ conductivity | 82.7 mS/cm* | * 50 °C, 1 M KOH |
| Swelling ratio | ≈ 30 % |
* Test conditions. Performance depends on cell hardware and operating conditions. Values marked “Target” are project targets. Full datasheet on request.
how to qualify
- Tell us your cell or stack format, the substrate type you need for catalyst-coated substrates (CCS), operating window (electrolyte, temperature, pressure) and test plan.
- We recommend a matched set (membrane, ionomer, OXYGN anode, H2GN cathode) and send the datasheet.
- Order a paid sample set and run your break-in, polarisation and durability protocol.
- Review the results with our team and agree formats, volumes and lead times for the next step.
AEM qualification pack
Product overview, recommended test protocol and spec summary as a PDF.
frequently asked questions
Is AionFLX™ really PFAS-free?
Yes. AionFLX™ membranes and ionomers are PFAS-free by design, which matters for buyers preparing for PFAS restrictions in the EU.
How is the membrane assembled?
Wet assembly is the validated assembly route for AionFLX™. Ask for the handling notes with the datasheet so your team uses the conditioning step that fits your stack build.
Which ionomer and electrodes should I pair it with?
We recommend AionFLX™ ionomer in the catalyst layers and OXYGN (anode) and H2GN (cathode) electrodes. Qualifying the matched set avoids pairing a PFAS-free membrane with a PFAS-based binder.
How do I get samples and prices?
Samples are paid and prices are on request. Use “Request samples” on this page; we reply personally with price, available sizes and lead time.
related products
AEM ionomers and binders
AionFLX™ ionomers
Matched PFAS-free binder for AEM catalyst layers, electrodes and inks.
Learn more →CRM-free anodes for AEM
OXYGN catalysts and electrodes (AEM)
CRM-free oxygen-evolution catalyst and coated anodes.
Learn more →CRM-free cathodes for AEM
H2GN catalysts and electrodes
CRM-free hydrogen-evolution catalyst and coated cathodes for AEM cells.
Learn more →AEM stacks and systems
HYScale AEM electrolyser stacks and systems
CRM-free AEM stacks on CENmat materials: 6 kW short stack validated; 100 kW system: production completed · in commissioning.
Learn more →Publicly funded projects with CENmat participation
- HYScale – coordinated by CENmat
- SWEETHY – CENmat as partner
- REDHY – CENmat as partner
- NEWELY – CENmat as partner
Next step
Paid samples. Prices on request. We reply personally. All products · AEM vs PEM iridium calculator