Electrolyzer Materials: Titanium Felt, Nickel Felt or Porous Titanium Plate
Electrolyzer materials come down to three positions: titanium felt or porous titanium plate on the PEM anode, nickel felt or mesh-reinforced nickel felt in alkaline and AEM stacks, and nickel mesh as the current collector. The wrong substrate does not cost you efficiency; it perforates within months.
Water electrolysis splits into two families: PEM, and alkaline (including AEM). The PEM anode runs in an acidic, oxygen-evolving environment where titanium is one of very few materials that survives; alkaline and AEM stacks work in caustic electrolyte, where nickel is the practical and far cheaper choice. The gas diffusion layer, electrode substrate and current collector differ in form, but all three demand uniform porosity, low resistance and no leaching into the electrolyte.
Where each material goes
| Material | Stack type | Position | Key figures |
|---|---|---|---|
| Titanium felt for hydrogen | PEM / AEM | Anode gas diffusion layer (PTL) | 0.25–1.0 mm thick, 50%–80% porosity |
| Porous titanium plate | PEM / AEM | Gas diffusion layer, gas distribution plate | Connected pores, rigid, no fibre shedding; porosity and rating to order |
| Nickel felt | Alkaline | Electrode substrate | Alkali-resistant, conductive, high porosity; thickness and areal weight to order |
| Mesh-reinforced nickel felt | AEM / alkaline | Large-area electrodes, GDL | Felt sintered onto expanded nickel mesh for porosity plus strength |
| Nickel mesh | AEM / alkaline | Current collector, electrode frame | 2–300 mesh, precise aperture |
Figures above are taken from the published product specifications; other ranges are available to drawing.
Three decisions that actually matter
Pick the stack type first
The PEM anode is acidic and oxygen-evolving, where nickel dissolves quickly and only titanium holds. Alkaline and AEM run on nickel at an order of magnitude lower cost. Get this wrong and the rest of the specification is moot.
Thickness trades against resistance
Titanium felt spans 0.25–1.0 mm: thinner lowers contact resistance, thicker holds up better under compression. Porosity runs 50%–80% — high porosity favours mass transport, low porosity gives more contact points and lower areal resistance.
Large electrodes need reinforcement
A single felt sheet sags and deforms over large areas. Mesh-reinforced nickel felt sinters the mesh into the felt, solving strength and conductive path together for megawatt-scale stack aspect ratios.
Matching products
Tell us the stack type (PEM, alkaline or AEM), the active area per sheet, and your thickness and porosity targets. We confirm the specification and quote within one working day.