At 2 A/cm², every milliohm of interfacial resistance in an electrolyzer stack costs 2 mV of cell voltage — 400 mV across a 200-cell stack — roughly 800 W of continuous additional power that generates heat instead of hydrogen. A single mesh-to-bipolar-plate interface can contribute 5–15 mΩ·cm² if the contact geometry is poorly optimized. At Jiangsu DZX Alloy Co., Ltd., we do not treat the electrical interface as an afterthought that sorts itself out under compression. We engineer the corrugation profile — the peak flat width, the contact point density, the strand cross-section, and the post-form annealing condition — to minimize the interfacial resistance between the mesh and every surface it contacts. Measured contact resistance on our optimized trapezoidal corrugated mesh is consistently below 2 mΩ·cm² at 1.5 MPa compression — verified by four-wire measurement on every production lot, not estimated from bulk resistivity.

The Hidden Voltage Loss — Where Interfacial Resistance Lives

In a typical alkaline electrolyzer cell, the mesh electrode spans the gap between the bipolar plate and the membrane or diaphragm. Current flows from the bipolar plate, through the mesh-to-plate interface, through the mesh strands, through the mesh-to-electrode interface, and into the electrode catalyst layer. Each interface is a discrete contact — not a continuous area — and each contact point has a constriction resistance where the current crowds into a small contact spot.

The bulk resistance of the nickel mesh itself is negligible. A 1 mm thick nickel mesh with 50% open area at 2 A/cm² contributes roughly 0.5 mV of ohmic drop — barely measurable. The interfacial resistance at the two mesh contact surfaces — plate and electrode — dominates. If each interface adds 5 mΩ·cm² at 2 A/cm², the combined interfacial voltage drop is 20 mV — 40× the bulk mesh contribution. This is the voltage loss that mesh geometry controls, and it is the loss that most mesh specifications ignore entirely.

Corrugation Geometry vs Interfacial Resistance — The Engineering Trade-Off

These are measured values, not literature estimates. Four-wire (Kelvin) measurement on 50 mm × 50 mm mesh samples compressed between nickel platens at controlled pressure. Measured per production lot. Reported on your certificate of conformance if requested. Your actual interfacial resistance will depend on your bipolar plate surface finish and your compression uniformity — but the mesh contribution is quantified.

Key Features & Benefits

• Contact resistance measured on your mesh, not estimated from a textbook — Most mesh suppliers quote the bulk resistivity of pure nickel (~7 × 10⁻⁸ Ω·m) and let you calculate the rest. The bulk resistivity tells you nothing about interfacial resistance — which is dominated by constriction at discrete contact points. We measure contact resistance directly on a four-wire test fixture with nickel platens at your stack compression pressure. The measured value — not a calculation — goes into your cell voltage model.

• Trapezoidal corrugation — engineered contact area, not line contact — Sinusoidal corrugation is cheaper to tool and easier to form — which is why most mesh suppliers default to it. But at the peak of a sine wave, the mesh contacts the adjacent surface along a line — theoretically zero contact area, practically a very narrow band. Trapezoidal corrugation provides a flat contact zone 0.3–0.5 mm wide at every peak and valley — 3 to 5 times the contact area of sinusoidal at the same pitch. The interfacial resistance difference is measurable and significant above 1 A/cm².

• Annealed — resistance that stays low for the life of the stack — Work-hardened mesh may show acceptable initial contact resistance during your single-cell test. But over the first 1,000–2,000 hours at 80°C under sustained compression, the residual forming stress relaxes — the peak geometry shifts slightly — the contact area decreases — the interfacial resistance increases. Annealed mesh has zero residual stress. The peak geometry is stable. The contact resistance on day one is the contact resistance on day 10,000.

• Nickel-only processing — no foreign metal at the contact interface — If the mesh surface carries even a thin layer of iron contamination from tool steel dies, that iron forms a high-resistance oxide at the contact interface under anodic conditions. The interfacial resistance increases — not from mesh geometry, but from surface contamination. DZX tooling is nickel-compatible. The contact surface is nickel — not nickel with an iron-rich surface layer that oxidizes over time.

• Uniform peak height — uniform contact pressure across the cell — If the corrugation amplitude varies by ±0.05 mm across the sheet, the contact pressure varies by approximately ±15% at the peaks — because the taller peaks carry more of the compression load and the shorter peaks carry less. Non-uniform contact pressure produces non-uniform interfacial resistance — and non-uniform current density. Our gear-forming process with precision-ground rolls holds amplitude tolerance to ±0.03 mm across the sheet width. Contact pressure uniformity is engineered — not hoped for.

• Electrical characterization data — your model, our measurements — In addition to contact resistance, we can provide: through-plane resistivity of the compressed mesh (relevant for stack voltage modeling), in-plane sheet resistance (relevant for lateral current distribution analysis), and contact resistance stability over time at temperature (relevant for lifetime voltage drift prediction). These measurements use your mesh specification at your stack conditions — not generic values from a material property database.

About DZX — Electrical Performance Through Metallurgical Control

Jiangsu DZX Alloy Co., Ltd. has manufactured pure nickel products since 2002. Over two decades of working exclusively with nickel, we have learned that the electrical performance of a mesh component is determined by three factors — in order of importance: the contact geometry, the surface condition, and the bulk material. Most mesh specifications address only the bulk material — by specifying the nickel grade. The contact geometry and surface condition — which together account for roughly 80% of the total interfacial resistance — are left to the manufacturing process. At DZX, we control all three. The geometry through precision-ground corrugation tooling and amplitude SPC. The surface condition through nickel-only processing that prevents foreign metal contamination. The bulk material through ingot chemistry control that we have refined since 2002. The result is mesh that performs electrically as designed — not mesh whose electrical performance is an accidental outcome of a process optimized for throughput rather than resistance.

• 12,000 m² nickel-only facility — melting, wire drawing, strip rolling, weaving, expanding, corrugating, annealing. Every surface that contacts the metal is nickel-compatible — no iron contamination at the contact interface.

• Contact resistance measurement capability. Four-wire Kelvin method on nickel platens at controlled compression pressure. Measured values — not literature estimates — for your cell voltage model.

• Custom trapezoidal and sinusoidal corrugation. Pitch 2.0–8.0 mm. Amplitude 0.5–3.0 mm. Precision-ground forming rolls. Amplitude SPC with ±0.03 mm tolerance.

• ISO9001 with full melt-to-mesh traceability. SGS-accredited. Contact resistance data available on certificate of conformance.

Chemical Composition — Four Pure Nickel Grades

Chemistry certified from ingot through finished mesh. Surface chemistry consistent with bulk — verified in a nickel-only processing environment. Grade selection affects both corrosion resistance and bulk resistivity (higher purity = slightly lower bulk resistivity, but the effect on total interfacial resistance is small compared to contact geometry effects).

Third-party verification by SGS, BV, or TÜV. Contact resistance data package available for stack electrical design verification.