# FR4 Fiberglass Board: The Preferred Insulation Material for New Energy Equipment
What Is FR4?
FR4 (Flame Retardant 4) is a composite insulation board made of glass fiber cloth as the reinforcing material and epoxy resin as the matrix. It is currently one of the most widely used insulation base materials in the electronic and electrical industries. The "FR" in its name stands for Flame Retardant, and "4" represents the glass fiber-reinforced epoxy resin system.
Dongguan Chaorong Electronics Co., Ltd. provides precision machining services for FR4 fiberglass boards in various specifications, with a thickness range of 0.5mm–50mm, capable of processing various insulation structural components according to drawings.
FR4 Core Performance Parameters
| Performance | Typical Value | Test Standard |
|---|---|---|
| Dielectric Strength | ≥20 MV/m | IEC 60243 |
| Volume Resistivity | ≥10¹⁰ Ω·m | IEC 60093 |
| Flame Retardancy | UL94 V-0 | UL 94 |
| Flexural Strength | ≥340 MPa | IEC 60893 |
| Operating Temperature | -50°C ~ +130°C | — |
| Water Absorption | ≤0.10% | IEC 60068 |
| Glass Transition Temperature (Tg) | 130°C / 170°C (High-Tg) | IEC 60249 |
Key Applications in the New Energy Sector
1. New Energy Vehicle (NEV) Insulation Components
- Battery Pack Insulation Separators: Isolates cells and modules, prevents short circuits, withstands voltages above 600V - BMS Insulation Baseplate: High-Tg FR4 (Tg≥170°C) ensures dimensional stability in high-temperature environments - EV Charger Internal Insulation Brackets: Withstands mechanical vibration with stable long-term insulation performance
2. Photovoltaic Inverters
- IGBT Module Insulation Gaskets: High-thermal-conductivity FR4 composite balances insulation and heat dissipation - Busbar Insulation Separator Plates: Prevents arcing between high-voltage busbars
3. Energy Storage Systems (ESS)
- Cell Spacer Plates: V-0 flame retardancy effectively prevents thermal runaway spread - Module End-Plate Insulation Layer: Resistant to electrolyte corrosion with long-life design
Why Choose FR4 Over Other Insulation Materials?
| Material | Advantages | Limitations |
|---|---|---|
| FR4 Fiberglass Board | Excellent all-around performance, good machinability, moderate cost | General thermal conductivity |
| Polyimide (PI) | Higher temperature resistance (>250°C) | 5–10× higher cost |
| Phenolic Paper Board (FR1/FR2) | Lower cost | Poor mechanical strength, high water absorption |
| Ceramic Insulation Board | Good thermal conductivity | Brittle, difficult to machine |
For most new energy application scenarios, FR4 achieves the best balance between performance and cost.
Chaorong Electronics FR4 Machining Capabilities
- Precision Cutting: CNC milling, dimensional tolerance ±0.05mm - Drilling: Minimum hole diameter 0.8mm, positional accuracy ±0.1mm - Surface Treatment: Edge grinding, chamfering, silk-screen marking - Fast Delivery: Standard parts in 3–5 days, custom parts in 7–10 days
For FR4 fiberglass board samples or bulk quotes, contact Dongguan Chaorong Electronics Co., Ltd. We provide professional insulation material solutions for the new energy and power electronics industries.