C18070 Applications: EV Battery Connectors, Photovoltaics, Relays and Fuse Boxes

The previous article set out the numbers behind C18070. This one shows where they are put to work. The common thread is a part that must carry a large current, stay stable when hot, and often be formed into a complex shape — the exact combination the alloy is built for.

High-voltage battery connectors

Electric-vehicle battery systems move large currents through compact connectors, and every milliohm of resistance turns into heat inside a sealed pack. C18070's conductivity of 78–83% IACS keeps that resistive heating down, while its stress retention of at least 85% at 200°C for 1000 hours means the contact keeps its clamping force through years of hot cycling. The good bendability lets the same part be formed into the tight geometry a pack demands. This combination is why the alloy is specified for high-voltage battery interconnects.

Automotive relays and fuse boxes

Relays switch current thousands of times and must not lose contact force; fuse-box terminals sit in hot engine-bay environments and carry continuous current. Both need conductivity to avoid heating and relaxation resistance to stay tight over time. C18070 provides both, and its formability suits the stamped busbar and terminal shapes these assemblies use.

Photovoltaic breakers and connectors

Solar hardware runs current continuously for decades outdoors, so connectors and breaker parts must conduct efficiently and hold their contact force through daily thermal cycling. The alloy's high conductivity limits losses across the many connections in an array, and its stable behaviour at temperature suits the long service life these installations are designed for.

Consumer-electronics contacts

In connectors, sockets and small relays for consumer devices, C18070 offers conductivity for signal and power integrity together with the formability needed for miniaturised, complex contact shapes. Where a part must be both highly conductive and intricately formed, the alloy's 0t bendability in the softer temper is a practical advantage.

Matching the alloy to the part

Across these uses the pattern is consistent: C18070 is chosen when a part must carry a large current with minimal heating, hold its contact force at temperature, and be formed into a demanding shape. If a part needs only spring force, a spring alloy is better; if it needs only conductivity with no forming or heat, plain copper is cheaper. Shanghai Xinye Metal Material works with customers in the automotive, PV and electronics sectors to match temper and gauge to the specific connector rather than supplying one grade for every job.

Frequently asked questions

Is C18070 suitable for EV battery connectors?

Yes; it is one of its core uses, combining high conductivity with stress retention at temperature and good formability.

Can C18070 be used in photovoltaic connectors?

Yes. Its high conductivity and stable behaviour over long hot service suit the decades-long duty of solar hardware.

Why choose C18070 for a high-current contact?

Because it keeps resistive heating low through high conductivity while holding contact force at temperature — and can still be formed into a complex shape.

Next in this series: Choosing the right C18070 temper (R400–R580), and how the switch from C18080 affects cost.