Industrial graphene coating of low-voltage copper wires for power distribution

TL;DR

This paper presents a rapid, scalable graphene coating process for low-voltage copper wires that enhances oxidation resistance and electrical conductivity, enabling cost savings and long-term performance improvements in power distribution applications.

Contribution

It introduces an industrial-compatible CVD method for coating copper wires with graphene, improving their electrical and oxidation properties for practical power distribution use.

Findings

Graphene-coated copper wires show up to 3% conductivity increase after 24 months.

The coating process induces changes in copper crystallinity, enhancing conductivity.

The roll-to-roll CVD process enables in-line, large-scale production of coated wires.

Abstract

Copper (Cu) is the electrical conductor of choice in many categories of electrical wiring, with household and building installations being the major market of this metal. This work demonstrates the coating of Cu wires - with diameters relevant for low voltage (LV) applications - with graphene. The chemical vapor deposition (CVD) coating process is rapid, safe, scalable and industrially compatible. Graphene-coated Cu wires display oxidation resistance and increased electrical conductivity (up to 1% immediately after coating and up to 3% after 24 months), allowing for wire diameter reduction and thus significant savings in wire production costs. Combined spectroscopic and diffraction analysis indicate that the conductivity increase is due to a change in Cu crystallinity, induced by the coating process conditions, while electrical testing of aged wires shows that graphene plays a major role in maintaining improved electrical performances over long periods of time. Finally, graphene coating of Cu wires using an ambient pressure roll-to-roll (R2R) CVD reactor is demonstrated. This enables the in-line production of graphene-coated metallic wires as required for industrial scale-up.