How to Determine the Right Busbar Thickness for Your Application

Introduction

Busbars play a crucial role in electrical and battery systems by efficiently distributing power while minimizing energy loss. Choosing the correct busbar thickness is essential for ensuring optimal performance, safety, and cost-effectiveness. This article outlines the key factors that determine busbar thickness and provides general guidelines for different applications.

Key Factors in Determining Busbar Thickness

1. Current Carrying Capacity (Ampacity)

- The higher the current, the thicker the busbar should be to reduce electrical resistance and prevent overheating.

- Copper busbars typically carry 1.2–1.6 A per mm2, while aluminum busbars carry 0.8–1.2 A per mm2 due to lower conductivity.

2. Material Type (Copper vs. Aluminum)

- Copper busbars offer better conductivity, allowing for thinner designs compared to aluminum.

- Aluminum busbars are lighter and more cost-effective but require a larger cross-section to carry the same current.

3. Voltage Drop Consideration

- A thicker busbar reduces voltage drop, ensuring stable power distribution.

- Voltage drop should typically be less than 3% for efficient systems.

4. Thermal Management

- Heat dissipation is critical in high-power applications.

- Thicker busbars help distribute heat more effectively, reducing overheating risks.

5. Mechanical Strength & Flexibility

- In EV battery packs, thinner, flexible busbars help accommodate battery movement.

- In power systems, thicker busbars provide better rigidity and durability.

Recommended Busbar Thickness for Different Applications

Selecting the right busbar thickness depends on multiple factors such as current capacity, material, voltage drop, heat dissipation, and mechanical strength. Copper is preferred for high-efficiency systems, while aluminum is an economical alternative with increased thickness. By carefully evaluating these parameters, engineers can optimize busbar performance for their specific needs.