Automotive BusBar: Analysis of High Voltage Transmission Core Components

Unlike traditional fuel vehicles, the voltage level of new energy vehicles is significantly higher, so conventional high-voltage components such as high-voltage connectors, high-voltage wiring harnesses, fuses, relays, etc. have attracted much attention. However, in high-voltage and high-current transmission scenarios, there is another type of non-standard core component that plays an indispensable role, which is the core subject of this article - the new energy vehicle busbar, also commonly referred to as the Automotive BusBar in the industry.

Busbar is not an emerging product. Since the invention of electricity and its development towards high voltage and high current transmission, busbars have been accompanied by it and widely used in various fields such as power, communication, new energy vehicles, energy storage, and the military industry. This article will systematically review the knowledge related to busbars in the new energy industry, covering material classifications such as copper bars, aluminum bars, and copper-aluminum composite bars, processing property classifications such as hard bars, soft bars, and soft-hard overlap bars, as well as key processes such as soft-hard copper bar overlap welding. It also involves an analysis of the application characteristics of EV BusBar.

From the perspective of material, Automotive BusBars are mainly divided into copper bars and aluminum bars, with other special materials being relatively rare. From the perspective of stress relief function, it can be divided into soft busbars (copper bars, aluminum bars) and hard busbars (copper bars, aluminum bars). Among them, the overlap technology threshold between hard busbars is relatively low, and in the market circulation, it is mostly priced based on weight. It is worth noting that the Tin Plated Copper BusBar for EVs exhibits superior corrosion resistance and conductivity stability in high-voltage scenarios of new energy vehicles through its special coating process.

Based on the application requirements of new energy vehicle battery packs and energy storage battery systems, the classification of BusBar Automotive and copper aluminum structural components can be further refined: according to materials, busbars can be divided into various types such as copper bars, aluminum bars, copper aluminum composite bars, and copper aluminum welded busbars; According to the processing properties, it can be divided into hard bars, soft bars, and soft hard overlapping bars. It should be noted that "bar" originates from the English word "bar" and belongs to the English loanword in Teochew, specifically referring to the connection method of battery modules and copper bar components.

Busbar and stacked busbars have many core advantages: firstly, they have a compact structure that can optimize the internal space layout of the equipment reasonably; Secondly, the installation is convenient and precise, and the subsequent maintenance is efficient; Thirdly, it has low impedance and excellent heat dissipation performance, which can effectively reduce the temperature rise of the entire power system; Fourthly, the characteristics of low inductance and high capacitance can significantly reduce peak voltage, effectively protect electronic components such as IGBT, and reduce system noise, battery interference, and radio frequency interference; Fifthly, the input and output methods are flexible and can be efficiently integrated with components such as connectors, wiring harnesses, rivets, etc; Sixth, the current density can reach 4A/mm ², which can effectively reduce the number of PCB layers when integrated with PCB; Seventh, it supports multi-layer stacking design, can input different voltages to each layer, and also has EMI shielding function. These physical characteristics enable it to adapt to higher standards of automated assembly requirements in the field of new energy vehicles. For example, in the application of the Car Battery BusBar, its advantages of easy installation and strong integration are fully utilized.

Busbar Insulations has excellent mechanical properties, good conductivity and thermal conductivity, strong corrosion resistance, as well as advantages such as good electroplating, brazing, and easy formability. These characteristics enable it to be processed into various power transmission and transformation equipment and electrical equipment, and to be widely used in the field of power. Among them, Insulated Bus Bar, with its special insulation treatment process, exhibits higher safety and stability in high-voltage scenarios, effectively reducing the risk of leakage.

The Insulated Bus Bars are a multi-layer composite structure connection busbar, with the core connection method being busbar connection. The battery terminals or module poles are connected in series or parallel through welding or bolt fastening; In addition to the field of new energy vehicles, composite busbars are widely used in power and hybrid traction equipment, cellular communication, base stations, telephone exchange systems, large network equipment, large and medium-sized computers, power switch systems, welding systems, military equipment systems, power generation systems, power conversion modules of electric equipment, and other scenarios. Among them, the application of New Energy Vehicle Film Capacitor BusBar in power conversion modules is particularly critical.
 

Focusing on the new energy vehicle industry, high voltage and high current are clear development directions, while the requirements for product integration and space miniaturization continue to increase, which puts higher standards on the performance of Automotive BusBar. The core issues currently being focused on in the industry include: how to ensure the reliability and durability of the busbar; Scientific determination method for the current carrying capacity of mother row; How to adapt the busbar design to the increasingly high automation assembly requirements of core components such as new energy vehicles, power batteries, motors, and electronic controls based on industry characteristics; The value of mother buses in new energy vehicles per vehicle; Competitive analysis of key enterprises in the global mother row industry; The future development direction and key technological breakthroughs of mother volleyball; The market prospects of the entire busbar industry, etc. Among them, in Film Capacitor Busbar for HEV / EV Motor Control Unit,Copper Busbar for DC link EV Film Capacitor, the balance between performance optimization and cost control in segmented application areas will become the key to the core competitiveness of enterprises.