Aluminum Application Trends and Technical Analysis in New Energy Vehicle Electrical Systems

With the rapid development of the new energy vehicle industry, lightweighting materials and optimizing electrical conductivity have become two key areas of focus. In recent years, more and more automakers have begun replacing copper with aluminum, particularly in electrical connectors and conductor systems, such as aluminum busbars and flexible aluminum connections. Some traditionally believe that using aluminum is cutting corners, but from the perspective of materials science and industrial practice, the use of aluminum does not compromise standards but rather conforms to the technological development trend of high efficiency, lightweighting, and energy conservation in the new energy industry.

 

 

 

 

Copper has been one of the earliest metals used by humans since ancient times, possessing excellent electrical conductivity and mechanical strength. Although aluminum was discovered later, it has gradually become a key material in industrial manufacturing due to its extremely high crustal reserves and excellent specific strength.

 

Density Comparison: Copper has a density of approximately 8.9×10³ kg/m³, while aluminum has a density of approximately 2.7×10³ kg/m³, only one-third that of copper.

 

Price and Resource Advantages: Aluminum's price is about one-quarter that of copper, and its reserves are approximately a thousand times greater.

 

Conductivity Difference: Aluminum's conductivity is approximately 61% of copper's, but due to its significantly lighter weight, it offers more economical conductivity per unit mass for the same current-carrying capacity.

 

Therefore, high-performance aluminum alloy busbars such as 6061 aluminum busbars, 6101 aluminum busbars, and 6101 T61 aluminum busbars are widely used in automotive, rail transit, energy storage, and charging infrastructure.

 

 

According to statistics from international research institutions, every 10% reduction in vehicle weight can improve fuel efficiency by 6% to 8%, and every 100 kg reduction in curb weight can reduce fuel consumption by 0.3 to 0.6 liters per 100 kilometers.

 

The widespread use of aluminum in structural components, wiring harness systems, and conductive parts is an effective means of achieving lightweighting.

 

Replacing steel with aluminum in vehicle bodies can reduce weight by 30%-40%.

Aluminum engines can reduce weight by approximately 30%.

Aluminum radiators are 20%-40% lighter than copper radiators.

 

In electric vehicles in particular, the lightweight properties of aluminum alloys can significantly extend driving range. For example, an all-aluminum structure can reduce vehicle weight by 200 kg and increase driving range by approximately 5.5%. This is particularly important for new energy vehicles, where battery costs are high.

 

 

 

 

The electrification trend in new energy vehicles, with its high current density and rising voltage levels, places higher demands on conductor heat dissipation and weight control. Consequently, aluminum busbars and their derivatives are widely incorporated into system designs.

 

1. Aluminum Busbars

Aluminum busbars play a critical role in energy transmission between power batteries, high-voltage distribution systems, and electric drive systems. Compared to copper busbars, aluminum busbars offer the following advantages:

 

Weight reduction of approximately 50%-70%;

Cost reduction of approximately 30%-40%;

Easy processing, welding, and surface tinning.

 

Tin-plated aluminum busbars effectively address the issue of increased contact resistance caused by aluminum surface oxidation, improving connection stability and corrosion resistance.

 

2. Flexible Aluminum Connections

To address vehicle vibration and thermal expansion and contraction stresses, flexible aluminum connections (or aluminum flexible connections) are widely used in modern manufacturing.

 

These products significantly improve mechanical flexibility and electrical safety in power battery modules, energy storage systems, and DC/DC converter modules.

 

3. Customized Aluminum Busbars

For different vehicle models and current levels, the busbar's cross-sectional area, bending method, hole layout, and coating process all require customization. A high-quality aluminum busbar manufacturer can provide integrated solutions from material selection, molding, surface treatment, insulation, and packaging.

Typical products include:

6061 aluminum bus bar (high-strength structural busbar)

6101 T61 aluminum bus bar (high-conductivity busbar)

Tin-plated aluminum bus bar (corrosion-resistant busbar)

 

 

 

 

Despite aluminum's many advantages, direct copper-aluminum connections still present challenges of electrochemical corrosion and thermal expansion mismatch. Because the potential difference between the two metal electrodes is approximately 1.7V, improper handling can easily lead to increased contact resistance, overheating, and even ablation.

 

Solutions include:

Using bimetallic transition joints;

Using tin- or silver-plated aluminum bus bars to inhibit oxidation;

Using specialized crimping or friction welding techniques to create a reliable connection interface.

 

The maturity of these technologies has significantly promoted the widespread use of aluminum busbar electrical power connectors and flexible aluminum connections in high-voltage systems of new energy vehicles.

 

 

With the rapid growth of new energy vehicles, global demand for aluminum conductors and busbars continues to rise. According to industry forecasts, by 2030, aluminum usage in new energy vehicles will more than triple compared to 2020.

 

In the future, aluminum busbar manufacturers will focus more on the following areas:

 

Using high-conductivity aluminum alloys (such as 6101 and 6061 series);

Implementing modular and intelligent busbar system design;

Promoting the development of green production and recycling systems.

 

With the maturity and standardization of production processes, customized aluminum busbars and aluminum flexible connections will become the mainstream choice for new energy vehicle electrical systems, further promoting the deep integration of lightweighting, electrification, and sustainable development.

 

 

Using aluminum is not cutting corners; rather, it represents an industry upgrade towards greater efficiency, lighter weight, and environmental friendliness. From aluminum busbars to flexible aluminum connections, and then to tin-plated aluminum bus bars and high-performance alloy series (such as 6101 T61 aluminum bus bar and 6061 aluminum bus bar), the application of aluminum in the electrical connection systems of new energy vehicles has become an important support for the global manufacturing industry to move towards intelligence and sustainability.