Advancements in Electric Vehicle Efficiency through Hybrid Conductors
Norway has seen a notable increase in electric vehicles (EVs), each equipped with a variety of electrical conductors that significantly influence the total weight of these vehicles.
The Challenge with Copper Conductors
“Traditionally, copper has been the material of choice for electrical conductors due to its exceptional conductivity, malleability, and durability,” explained Jørgen A. Sørhaug, a Ph.D. researcher at NTNU.
While copper excels in performance as an electrical conductor, it carries a substantial drawback with its high mass density, making it relatively heavy.
“Consequently,” Sørhaug noted, “the weight contribution from copper can be considerable in electric vehicle designs.”
Exploring Aluminum as an Alternative
Weight is crucial when considering the energy efficiency and operational range of electric vehicles; thus reducing this weight can yield significant benefits. The question arises: what alternative materials can be utilized without heavily relying on copper?
“Aluminum emerges as a viable substitute for copper,” said Sørhaug. “It offers nearly equivalent conductivity alongside strong formability and structural integrity—especially when alloyed with other elements—and importantly is much lighter than copper.”
This implies that substituting some amount of copper in electrical wiring with aluminum could lead to both lighter configurations and improved energy efficiency within EVs—a pursuit currently being investigated by Sørhaug and his team during his doctoral research.
Their efforts focus on developing hybrid electrical conductors composed of both aluminum and copper.
“Our initiative includes creating hybrid conductors via welding techniques that effectively combine these two metals while maintaining thorough testing protocols,” expressed Sørhaug.
The Role of Cold Welding Techniques
Crafting high-performance conductors presents hurdles; however, employing cold welding techniques allows us to merge beneficial attributes from both metals without sacrificing conductivity.
This method engages aluminum and copper at an atomic level during bonding—the challenge arises because increased temperatures tend to promote undesirable brittle intermetallic crystals at their junctions which exhibit inferior conductive properties compared to their pure metal counterparts.
“We explored cold welding methods utilizing our patented Hybrid Metal Extrusion & Bonding (HYB) approach,” said Sørhaug whose team conducted extensive analyses using various types of electron microscopy including precision electron diffraction analysis among others—though not necessary for general understanding—the findings are promising.”
“Our results indicate that our process outperforms traditional cold welding methods by promoting thinner intermetallic layers between metals which enhances mechanical strength alongside ensuring stable conductive qualities,” he further explained.
The Temperature Dilemma
Further investigation is needed before widespread adoption can occur regarding aluminum’s role as a partial replacement for copper within electrical components since pure aluminum inherently lacks mechanical strength relative to its counterpart—copper poses challenges here due to this property disparity.
