Will BEV really drive demand for copper?

November 21, 2022

There was a general expectation that use in BEVs would lead to a significant increase in demand for copper, but how true is this?

All modern vehicles require a small amount of copper as a conductor in wiring, fittings, and other electrical equipment.

why copper? The best conductor is silver, but it is not economical due to its high cost. Copper also offers a durable yet flexible solution to flexibility requirements.Battery electric vehicles (BEV) use significantly more copper than internal combustion engine (ICE) vehicles and hybrid electric vehicles (HEV). The largest consumers of copper in BEVs are batteries, electric motors, and power electronics.Most of the copper is inside the battery. Most lithium-ion battery cells use copper foil as the anode current collector. Modernization in cell manufacturing technology has made copper foil thinner, often halving its thickness in the last two years.

Busbars are solid copper strips used to connect battery cells and modules. Automakers are changing the way cells are connected, and new cell packaging methods can greatly reduce the need for busbars.

The Battery Management System (BMS) is used for voltage leveling, diagnostics, and cell monitoring and requires wiring to connect to the battery modules. Several companies are researching wireless BMS, but not many automakers are working on setting it up.

Battery capacity, system voltage, cell integration method, and cell format are some of the variables that affect the amount of copper used in batteries.

As mentioned in , we expect the average battery pack size to at least remain flat. previous blog.

Prismatic cells generally use less copper for busbars than cylindrical or pouch cells, and even less for long-format ‘blade’ cells combined with module-less cell-to-pack technology. This reduces the number of busbars between cells and packs. Several automakers are working on the concept and estimate that at least half of all BEVs will use it by the end of the decade.The outside of the battery is full of thick, high-current copper cables. The charger cable draws current from the external charger port to the onboard charger and battery. Battery power connects the battery to the inverter. A motor cable connects the inverter to the electric motor.

Doubling the operating voltage can significantly reduce the copper used in busbars, charger cables, and motor cables. Several automakers are working on 800V architectures.Placing the electrical interface close to the required power cables further reduces the copper footprint.

The current trend is to incorporate the inverter and the electric motor into one unit, requiring only a short busbar to connect the two, rather than cable connections.

Elsewhere, motor coils or windings are used in all forms of electric motors. In general, copper usage depends on motor size and power, and similar to battery size, average motor power is expected to plateau.Additionally, this does not consider manufacturers substituting aluminum for copper depending on suitability for a particular component. It has half the conductivity of silver, but offers significant weight and cost savings over copper.

Summing up these pathways for copper reduction, we get: First generation BEVs certainly used a lot of copper, but over time there has been more efficient use of copper..