Copper-Aluminum Busbar Special Topic: Analysis Of Stripping And Optimization Technologies For Powder Dipping, Extrusion, And Dipping Processes

In the manufacturing of new energy equipment and electrical connection systems, copper-aluminum busbars (busbars) fulfill core functions of conductivity and connection. With the widespread application of new structural components such as PVC-dipping insulated busbars, plastic-dipping copper busbars, and insulated flexible copper busbars for power battery packs, achieving efficient and damage-free stripping while maintaining excellent insulation performance has become a key technical challenge in the industry.

 

 

In PVC-coated busbars and epoxy-powder-coated copper busbars, the insulation layer is commonly made of epoxy resin powder. Epoxy resin is a thermosetting plastic that no longer melts or softens after the initial heat cure. Therefore, when producing dip-insulated busbars or epoxy powder-coated busbars, once formed, the insulation layer is difficult to remove mechanically or thermally.

 

This means that if the metal conductors at both ends of the copper-aluminum busbar need to be exposed, this must be achieved through a masking process during the dipping busbar production stage.

 

 

 

When manufacturing Insulated Custom Copper Bus Bars with PVC Dipping, masking is typically performed before powder dipping to ensure that the metal connection areas at the ends are exposed. The process flow is as follows:

 

Masking:
After stamping, cleaning, and drying, the copper and aluminum busbars are covered with protective sleeves at both ends and sealed with high-temperature tape.

 

Sandblasting and Preheating:
The copper busbars are hung in a sandblasting line and then preheated in a mold at 195–225°C to enhance powder adhesion.

 

Powder Dipping:
The preheated copper busbars are picked up by a robot and dipped into epoxy resin powder for coating.

 

Demasking and Trimming:
After curing, the tape and protective sleeves are removed, and the edges of the plastic layer are manually trimmed.

 

Curing:
The product is hung in a 170–190°C oven for curing, ensuring a smooth and secure coating.

During this process, a high-temperature tape with a temperature resistance of 200°C is sufficient. Excessively high temperatures will result in adhesive residue.

 

 

Unlike thermosetting epoxies, custom-made plastic-dipping electric copper busbars and PVC-dipped insulated busbars often utilize thermoplastic materials such as PA12 or PVC. These materials can be softened by repeated heating, enabling controlled peeling and trimming.

 

1. Basic Process Flow

Circular Cutting: Circular cuts are made on the copper busbar insulation layer using a laser or knife.

Heating and Softening: Adjustable heating zones are used to uniformly raise the temperature of the plastic layer, achieving an easily peelable state.

Debonding and Stripping: Softened areas are removed mechanically or manually.

 

This method is widely used during the processing of soft connection copper busbars and busbar supports, ensuring the metal conductors remain intact.

 

2. Heating and Circular Cutting Sequence Control

If the bond between the copper and plastic layers is weak, preheating should be performed before circumferential cutting. If the bond is strong, circumferential cutting can be performed before heating. Some equipment, such as the "three-station peeling machine," automatically controls temperature and synchronizes cutting, ensuring consistent busbar isolation and smooth edges.

 

 

Modern automatic peeling equipment can meet the needs of various specifications for plastic-dipping copper busbars and insulated custom copper busbars with PVC dipping. Typical performance is as follows:

 

Circular cutting range: Thickness 2–20mm, width 14–50mm, cutting length 10–100mm, with an accuracy of up to 0.02mm;

 

Heating Control:

The temperature range can be customized according to the project, with the maximum temperature monitored in real time by a sensor.

The heating length can be controlled up to 100mm to ensure uniform temperature distribution.

The recommended preheat temperature for the PA12 extrusion layer is approximately 130°C.

The PVC coating layer is controlled within a range of 60–120°C, depending on the hardness.

After debonding, the equipment automatically collects waste to prevent contamination of the metal body of the product.

 

 

 

Products such as PVC Dipped Insulated Bus Bars, Custom Made Plastic Dipping Electric Copper Bus Bars, and Dip Insulated Bus Bars used in new energy and electrical connection systems generally must meet the following standards:

 

Appearance Quality

The surface must be smooth and flat, free of defects such as bubbles, pitting, and delamination.

No insulation residue or burrs. Inspection light intensity ≥ 500 lux, inspection distance 30–50 cm.

 

Dimensional Accuracy

According to GB/T 1804-2000, the tolerance is ±0.5 mm for lengths ≤ 100 mm and ±1.0 mm for lengths 100–400 mm.

 

Surface Scratch Control

Should not affect electrical conductivity. Scratches must be ≤ 5 mm in length and ≤ 0.1 mm in width.

Roughness (Ra ≤ 3.2) and flatness (≤ 0.2 mm) must be tested.

 

 

Overall, epoxy powder-coated thermoset dip-insulated busbars are difficult to mechanically peel and require masking prior to powder dipping. Plastic-dipping copper busbars and PVC-dipping insulated busbars made of PVC or PA12 materials, on the other hand, can be efficiently trimmed using temperature-controlled peeling and automated cutting equipment.

 

In the future, with the advancement of new energy storage, electric vehicle battery systems, and high-voltage electronic control modules, the precision insulation technology of insulated flexible copper bus bars for power battery packs and PVC-coated bus bars will be further upgraded. Intelligent peeling equipment, modular busbar supports, and more environmentally friendly insulation materials will become the main directions of industry development.

 

Through continuous optimization of process details and quality control, Dipping Busbar for Connection and Plastic-dipping Electric Copper Busbar Custom Made will achieve higher safety, durability, and manufacturing consistency, driving the electrical connection industry towards a new stage of intelligent and green manufacturing.