High Conductivity Al/Ni Composite Strip Precision Size for 21700 Connections

DLX precision Aluminum-Nickel composite strips (Al/Ni Bimetal Strips) are specialized composite ribbon materials manufactured via advanced continuous solid-state cold rolling and diffusion-bonding technology. Designed specifically for cylindrical cell tabs (connecting the aluminum positive shell/terminal to nickel/copper busbars), our Al/Ni strip eliminates the formation of brittle intermetallic compounds (Al3Ni), ensuring minimal electrical resistance (≤0.028 μmΩ·m equivalent), zero delamination under intense vibration, and extended battery cycle life.

Conventional fusion welding between dissimilar aluminum and nickel alloys generates brittle intermetallics, high interface electrical resistance, and galvanic corrosion risks. DLX utilizes a multi-pass heavy-reduction cold rolling and precision vacuum thermal bonding process that creates an atomic-level metallurgical bond between 1050/1060 high-purity aluminum and Ni200/N6 pure nickel. The resulting transition zone is 100% homogeneous, ensuring no micro-voids, no delamination during subsequent 90°/180° stamping or bending, and maximum current throughput.

Automated module assembly lines for 21700 battery packs require exact dimensional stability and clean edges to prevent short circuits and laser reflection faults. DLX provides custom slitting with width tolerances down to ±0.05 mm and edge burr heights <0.01 mm. The nickel side is optimized for high-reliability resistance spot welding and ultrasonic welding to nickel-plated steel/copper busbars, while the aluminum side provides optimal laser weldability to aluminum cell terminals.

• Zero-Resistance Interfacial Bond: Atomic-level solid-state metallurgical composite layer guarantees continuous electron flow, lowering temperature rise across cell connections during fast charging (>3C).
• Superior Stamping & Forming Flexibility: High ductility allows 180° bending, multi-step deep drawing, and complex terminal shape stamping without layer separation or edge peeling.
• Dual Weldability Optimization:
  • Aluminum Surface: Tuned laser absorption for fiber/blue laser welding to battery aluminum caps.
  • Nickel Surface: Clean contact surface for micro-resistance spot welding or ultrasonic bonding to external circuits.
• Galvanic Corrosion Resistance: Continuous non-porous cladding blocks moisture ingress at the Al-Ni seam, maintaining structural integrity across extreme automotive operating conditions (−40°C to +85°C).
• High-Consistency Automated Feeding: Supplied in continuous pancake coils or spool-wound reels with tension-levelled flatness to prevent machine jamming on automatic tab-welding robots.

• 21700 & 18650 Cylindrical Battery Modules: Positive terminal current collector tabs in high-energy-density EV battery packs (Tesla-type module architectures).
• Commercial & Residential ESS (Energy Storage Systems): Interconnect busbars and flexible jumpers for solar storage battery racks requiring multi-year zero-maintenance reliability.
• High-Rate Power Tool Battery Packs: Connection tabs subject to high vibrational stress, thermal cycling, and high-amp pulse discharge.
• Electric Bicycles & Light Electric Vehicles (LEV): Lightweight bimetal connectors reducing overall pack weight while boosting electrical efficiency.
• BMS (Battery Management System) Voltage Sensing Terminals: High-accuracy signal tap tabs ensuring reliable voltage sampling without galvanic drift.

With over two decades of specialized focus in precision alloys and functional clad composites, DLX operates state-of-the-art continuous vacuum cladding mills and precision slitting centers. Every coil is produced under strict internal quality management protocols that surpass conventional industry standards.

• 100% In-House Rolling & Slitting: Full traceability from raw pure aluminum ingots and nickel cathode sheets to finished custom-slit ribbon reels.
• Rigorous Lot-by-Lot Interface Testing: Every master coil undergoes ultrasonic C-scan non-destructive testing, microsection SEM inspection, and 180° peel testing to guarantee 0% debonding.
• Rapid Prototyping & Custom MOQ: Dedicated tooling for quick-turn prototype batches (MOQ as low as 5 kg) and mass production capacity exceeding 50 tons/month.
• Export-Grade Packaging: Vacuum-sealed nitrogen packaging with desiccant and custom heavy-duty shockproof reel spools to prevent edge denting and oxidation during sea/air transit.

Direct fusion welding between aluminum and nickel produces brittle intermetallic compounds (such as Al3Ni and AlNi3), which increase electrical resistance and cause weld fracture under road vibration. DLX's cold-rolled Al/Ni composite strip features an atomic solid-state bond formed without liquid phase melting, ensuring uniform conductivity and superior mechanical durability.

We offer standard thicknesses from 0.15 mm to 0.30 mm (e.g., 0.20 mm total thickness with 0.10 mm Al+0.10 mm Ni), with custom slit widths from 3.0 mm to 50.0 mm. Custom cladding ratios (such as 70% Al / 30% Ni) can also be tailored to optimize weight and conductivity.

DLX conducts quantitative 180° peel tests and microscopic cross-sectional metallographic examinations on each production heat. The bonding interface strength exceeds the tensile strength of the base aluminum layer itself, meaning the parent metal will elongate and tear before the composite interface separates.

Every slit coil is degreased, edge-conditioned, and immediately packed in multi-layer moisture-barrier aluminum foil bags with active desiccant under nitrogen flushing, guaranteeing a minimum 12-month shelf life without surface tarnishing or weldability degradation.

Yes. Beyond continuous coil strips, DLX operates precision stamping and laser cutting workshops capable of delivering pre-formed, punched, and bent Al/Ni tab pieces with tight geometric tolerances (±0.05 mm) ready for automated pack assembly.