FR4 Material in EV Charging Stations

Introduction to FR4 Material FR4 is a composite insulation material made of woven glass fiber cloth and epoxy resin,...

Introduction to FR4 Material

FR4 is a composite insulation material made of woven glass fiber cloth and epoxy resin, cured under high temperature and pressure.
The term “FR” stands for Flame Retardant, and “4” indicates its grade under the NEMA standard.It offers excellent electrical insulation, mechanical strength, heat resistance, and flame retardancy (UL94 V-0) — making it an ideal material for EV charging equipment and power electronics.

Key properties of FR4:

Dielectric strength: up to 17 kV/mm

Continuous operating temperature: 130°C–150°C

Excellent moisture resistance and dimensional stability

High mechanical strength and machinability

UL94 V-0 flame retardant rating

Main Applications of FR4 in EV Charging Stations

1. PCB Substrate for Control Systems

The most common use of FR4 is as a printed circuit board (PCB) substrate.
In EV charging stations, FR4-based PCBs are found in:

Control boards

Power management modules

Communication units

Billing and monitoring circuits

Advantages:

FR4 ensures stable signal transmission, low dielectric loss, and long-term reliability under high temperatures and high current operation.

2. Power Module Insulation and Structural Support

In DC fast charging stations, FR4 is used for AC/DC and DC/DC conversion modules:

As insulating and supporting plates for power modules

Between high-voltage and low-voltage areas for isolation

As mounting and partition boards to maintain creepage distance

Why FR4?
Its high dielectric strength and thermal resistance prevent breakdown and leakage, ensuring electrical safety and stable operation.

3. Electrical Insulation and Protective Components

FR4 boards are machined into various insulating and protective parts:

Terminal covers and insulating gaskets

Relay base plates and support blocks

Isolation barriers and structural brackets

These components protect operators and devices from high-voltage arcing and electrical leakage, ensuring compliance with safety standards.

4. Heat Dissipation and Structural Integration

FR4 is also used as an electrically insulating layer between power devices and metal heat sinks.
In charging stations, it serves as:

Thermal isolation boards in power units

Support frames and mounting panels

Part of composite heat dissipation systems with aluminum base and silicone pads

This ensures mechanical stability and balanced heat distribution during continuous high-load charging.

Advantages of FR4 in EV Charging Equipment

Applications by Charger Type

Conclusion

With the rapid development of the electric vehicle (EV) industry, the demand for reliable and safe insulation materials in charging stations continues to grow.
FR4 epoxy glass fiber board plays a vital role in the control system, power module, and electrical protection of charging piles.

Its excellent electrical insulation, flame retardancy, and mechanical stability make FR4 one of the most trusted materials in EV charging equipment.