How PEM, AEM and AEL membranes are made
PEM, AEM and AEL membranes differ in chemistry and application, but their production follows similar steps: coating, curing, laminating and cutting. Each step affects how well the membrane performs and how long it lasts in an electrolyser or fuel cell. The sections below describe what each step demands.
Coating
Coating applies the ion-exchange material, as a liquid solution or dispersion of the membrane polymer, onto a substrate. The layer has to be uniform in thickness across the full width, because it determines both the ion-exchange capability and the mechanical properties of the membrane.
Curing
Curing solidifies and stabilises the coated layer. It gives the membrane its mechanical strength and helps it keep its structure under operating conditions, wet or dry. Temperature and time have to be controlled closely, so every metre of membrane gets the same treatment.
Cutting
Membranes and MEAs have to be cut to size to fit an electrolyser stack or fuel cell. The cut has to be clean, without frayed edges or delamination, and handling must not damage the material. Die cutting is often used in series production because it is fast and consistent. For development work and frequent format changes, a more flexible method can be the better choice.
MEA configurations: 3, 5 or 7 layers
A membrane electrode assembly (MEA) is built up in layers. A 3-layer MEA is the catalyst-coated membrane. A 5-layer MEA adds a gas diffusion layer on each side. A 7-layer MEA also adds the seals or subgaskets, the frame that seals the MEA in the stack. Every extra layer has to be laminated with the same alignment and pressure, without trapping air or damaging the catalyst layer.
From feasibility study to production
Every hydrogen project is different, and many start small. That is why we begin with your materials, membrane format and targets. Where useful, a feasibility study shows what is possible before a machine is built. From there we work out with you what an R&D or pilot machine needs to do, and how the process can grow towards production. Engineering, production and service are all in-house in Raalte, the Netherlands, so you work directly with the people who design and build the machine.
Where our lamination experience applies:
- Laminating: bonding layers under controlled pressure, temperature and alignment.
- Cutting: slitting, die cutting and sheet cutting of films and laminates.
- Winding and handling: roll-to-roll, roll-to-sheet and sheet-to-roll processes with controlled web tension.
Working on a hydrogen membrane or MEA project? Tell us about your materials and process. We are happy to think along at an early stage.