Innovative Designs Trim Weight From High-Voltage Components

A powerful splice 

Versigent proposed using an ultrasonic weld to hold the three cables directly together — eliminating the need for a heavy busbar — and encasing the splice with polyurethane reactor (PUR) to seal it. Versigent engineers then refined the design to use just enough PUR material to ensure the safety of the splice from an electrical and mechanical perspective. 

This approach reduced the weight by 20 percent and lowered the cost significantly. Performing the large weld required a new process, but our supplier agreed that there would likely be higher demand for this technology among other OEMs in the future and accelerated its own development.  

A lighter approach 

At the same time, Versigent proposed a lighter and more robust solution for the charging harness and other cables. The previous solution had used copper cabling insulated with silicon. The first part of Versigent’s solution was to switch the charging conductor from copper to aluminum, which reduced the weight of the conductor by 40 percent. Second, we proposed an optimized product design; the proposal moved from silicon insulation to cross-linked polyolefin (XLPO), which delivers performance at the temperatures that can be found in EVs, holds up well to abrasion over time and does not require 100 percent taping. 

Looking ahead, Versigent recommended transitioning the charging harness from aluminum cables to aluminum busbars. Because busbars are rigid, they require less packaging, such as brackets and cable channels, to hold them in place. The reduction in packaging, along with the improved heat dissipation of the busbar, brought the total weight savings to 50 percent. 

Fast results 

A key proof point for Versigent’s proposals was our electrothermal simulation capability. With basic knowledge of the vehicle’s engine cycles, the simulation was able to quickly show that the proposed products would meet the OEM’s requirements for heat tolerance. Later, we were able to confirm those projections in our labs. 

Importantly, Versigent engineers were able to provide these design options — including functional hardware — to the OEM for consideration in just six weeks. Because the splice design was a unique solution that had never been created before, we claimed a patent on it. 

Versigent will continue to help OEMs innovate with speed, delivering robust and creative solutions to solve their greatest challenges, particularly as they build out their EV offerings.