How to reduce weight and save money on automotive wiring and cables
Needless weight in hybrid and electric vehicles increases fuel consumption and decreases battery capacity and life. Reducing weight in the body structure of the car has the most potential, but you can save weight in electrical systems, too.
Electrical systems cover signal, power and battery applications, such as battery cables or wiring harnesses. Passenger vehicles have more cabling than you might imagine. As much as 30 kilograms in total. A good part of this amount is compounds of extremely thin wires used for electronical signal transmission or supply of electricity for very minor functions.
These cables, per meter, usually have more weight for insulation than of conducting material.
The other part consists of gross cables and bars used to connect the battery with the engine and the car body for grounding. For these more massive applications, aluminium is a real alternative.
Today, most of this is copper, which is the material traditionally used in battery cables and cable systems. In addition to the traditional structure of cable harnesses, in the very near future it will be necessary to interconnect the several battery modules to a single block in hybrid and pure e-cars.
Aluminium in automotive power supply
Aluminium is an excellent conductor of heat and electricity, and its density is around three times lower than copper. This means substituting aluminium for copper in automotive electrical systems can reduce the weight of the systems. Even when compensating for the higher resistance in aluminium compared to copper, the weight savings is more than 50 percent.
Aluminium also costs a lot less than copper and is far more transparent (i.e. less volatile) regarding price trends. Their performance is the same.
These are the areas in which aluminium is suitable:
- Battery cables
- Backbone technology
- Module connection in electrical cars
In battery cables, you can replace copper by using extruded solid aluminium rod that has been coated with either PA, PE or XPE coatings.