Analysis of Copper and Aluminum Busbar Insulation Processes: Powder Dipping, Extrusion, and Plastic Dipping Peeling Technologies and Applications

With the increasing safety and reliability requirements for new energy equipment and electrical systems, insulation treatment technology for copper and aluminum busbars has become an industry focus. Especially with the widespread use of products such as PVC-Dipped Insulated Busbars, Custom Insulated Copper Bus Bars with PVC Dipping, and PVC-Coated Bus Bars, achieving efficient and damage-free insulation stripping has become a key process challenge.

 

 

 

Among the many insulation treatment methods, powder dipping is the most widely used. The insulation layer is typically made of epoxy resin powder, a thermosetting plastic. This material softens and solidifies upon initial heating, but once solidified, it loses its meltability and cannot be stripped again by heat or mechanical means.

 

When producing products such as PVC-Dipped Insulated Bus Bars or Custom Made Plastic Dipping Electric Copper Busbars, if some metal areas need to be exposed, masking is often used before powder dipping. Masking is generally performed at both ends of the copper and aluminum busbars. High-temperature tape or protective sleeves are used to isolate the uncoated areas, creating a precise insulation boundary.

 

 

Masking Stage	After stamping, cleaning, and drying, the copper and aluminum busbars are wrapped with high-temperature protective bags at both ends and sealed with tape to prevent specific areas from being covered by powder.
Sandblasting and Preheating	The sandblasted busbar surface is uniformly roughened to improve insulation adhesion. It is then preheated in a mold at 195–225°C to create conditions for uniform powder adhesion.
Powder Dipping and Film Forming	A robotic arm immerses the preheated busbar into an epoxy resin powder bath to ensure coating absorption.
Demasking and Curing	After powder dipping, the tape and protective sleeves are immediately removed, and the edges are trimmed. The busbars are then cured in an oven at 170–190°C to stabilize the insulation layer.

 

While these thermoset materials offer excellent heat resistance and insulation properties, their irreversible molecular crosslinking makes subsequent processing or stripping extremely difficult, a common technical bottleneck in busbar isolation processes.

 

 

 

Unlike epoxy-dipped powders, extruded (PA12) and dipped (PVC) materials are both thermoplastics. These materials soften, melt, and reshape upon heating, making them suitable for localized peeling by controlling temperature and time during the manufacturing process.

 

The following processes are commonly used in the manufacture of insulated flexible copper bus bars for power battery packs, plastic-dipping copper busbars, or dipping busbars for connections:

 

Circular cutting:
Circular cutting of the insulation layer is performed using a mechanical tool or laser to ensure a clean cut.

 

Heating and softening:
The insulation layer is softened by controlled heating. PA12 material is generally preheated to 130°C, while PVC material is controlled between 60–120°C, depending on its hardness.

 

Debonding and Peeling:
After softening, the insulation layer is mechanically or pneumatically stripped to avoid damaging the metal core.

 

This process is not only suitable for standard busbars, but is also widely used for customized products such as the Plastic Dipping Electric Copper Busbar Custom Made and the Soft Connection Copper Busbar.

 

 

To improve processing efficiency and consistency, the industry generally uses a "three-station integrated peeling machine" to perform ring cutting, heating, and debonding operations. The equipment automatically adjusts parameters based on busbar size, material, and thickness, achieving precise debonding.

 

Ring Cutting Capacity: It can process busbars with thicknesses of 2–20mm, widths of 14–50mm, and lengths of 10–100mm, with an accuracy of ±0.02mm.

 

Heating Control: Real-time temperature detection ensures uniform heating and prevents overheating that could cause deformation of copper and aluminum.

 

Debonding: Automatically controls the debonding depth and position to prevent damage to the metal surface. It also centrally collects waste and maintains a clean work area.

 

This equipment is particularly suitable for mass production of PVC-dipping insulated busbars and insulated custom copper busbars with PVC dipping, enabling efficient automated production in applications such as power equipment, energy storage battery connections, and industrial busbars.

 

 

Appearance Inspection:
The surface should be flat and smooth, free of visible defects such as bubbles, burrs, delamination, and pitting.

Under 500 lux illumination, within a 30–50 cm inspection distance, no residual insulating material should remain.

 

Dimensional Control:
Performed in accordance with the medium tolerance grade of GB/T 1804-2000, ensuring that length and width accuracy meet design standards.

 

Scratch and Coating Inspection:
The surface must be free of scratches or pits that could affect conductivity. Minor scratches ≤5 mm in length and ≤0.1 mm in width are permitted, but their depth must not damage the coating or expose the base material.

 

Flatness and Roughness:
Flatness ≤0.2 mm and roughness Ra ≤3.2 are required to ensure stable conductivity and assembly performance.

 

These standards apply not only to traditional copper busbars, but also to the new PVC-coated busbars and plastic-dipping copper busbar product lines.

 

 

In modern electrical systems, busbar insulation technology is evolving from traditional epoxy powder coating to thermoplastic dipping and extrusion.

 

Epoxy powder coating is suitable for high-heat and high-strength environments, but stripping is difficult.

 

PVC or PA12 dipping/extrusion offers significant advantages in processability and repairability, making it more suitable for highly flexible applications such as soft connection copper busbars and insulated flexible copper busbars for power battery packs.

 

In the future, combined with the development of dipping busbar connection processes and automated equipment, the industry will further enhance the intelligent level of busbar insulation forming and stripping, providing more reliable solutions for busbar isolation and secure connections in new energy, energy storage, rail transit, and other fields.