Capacitor foil is a high-purity aluminum foil used in capacitors for electronics. It offers excellent electrical conductivity, corrosion resistance, and mechanical strength. This foil is widely used in power electronics, audio equipment, and home appliances.
Technical Specifications
| Parameter | 1060 | 1070 | 1100 | 3003 |
|---|---|---|---|---|
| Purity | 99.6% Al | 99.7% Al | 99.0% Al | 97.0% Al+Mn |
| Thickness (mm) | 0.02-0.04 | 0.025-0.045 | 0.03-0.055 | 0.04-0.055 |
| Temper | H18 | H18 | H18 | H18 |
| Tensile (MPa) | 140-180 | 130-170 | 120-160 | 150-190 |
| Etching Factor | 50-80x | 60-90x | 40-70x | 30-50x |
| Best For | Low-voltage | High-CV | General-purpose | High-strength |
Types of Capacitor Foils
1. Anode Foil
- High purity (1070/1060)
- Etched for 50-100x surface expansion
- Applications:
- Power supply capacitors
- EV charging systems
2. Cathode Foil
- 3003 alloy preferred
- Smooth surface finish
- Uses:
- Consumer electronics
- LED drivers
3. Solid Foil (Non-Etched)
- For:
- DC-link capacitors
- Snubber circuits
Key Applications
Electronics Industry
- Power supplies: Server PSUs, UPS systems
- Automotive: Inverters, battery management
- Renewable energy: Solar/wind converters
Consumer Devices
- Smartphone chargers
- Air conditioner PCBs
- IoT device power modules
Capacitor Foil Manufacturing Process
- Cold Rolling
- Achieves 0.02-0.055mm thickness
- ±0.001mm tolerance
- Heat Treatment
- Recrystallization annealing
- Controls H18 temper properties
- Surface Treatment
- Chemical etching (for anode foil)
- Formation coating (Al₂O₃ layer)
Performance Comparison
| Feature | Anode Foil | Cathode Foil |
|---|---|---|
| Surface Area | 50-100x base | 1-2x base |
| Voltage Rating | 6-600V | ≤100V |
| Cost | $$$ | $$ |
Frequently Asked Questions
Q: Can you make capacitors with regular aluminum foil?
A: No – Requires:
✔ Ultra-high purity (≥99.6%)
✔ Precision thickness control (±1μm)
✔ Specialized etching/forming
Q: Mylar vs. aluminum foil capacitors?
A:
| Type | Mylar Film Capacitor | Aluminum Electrolytic |
|---|---|---|
| Dielectric | Plastic film | Oxide layer + liquid electrolyte |
| Best For | Signal circuits | Power filtering |
Q: Capacitor lifespan?
A: 2,000-15,000 hours depending on:
✔ Operating temperature (↓10°C = 2x life)
✔ Ripple current load
✔ Electrolyte quality
Q: Why 3003 alloy for cathodes?
A: Manganese addition improves:
→ Mechanical strength
→ Winding performance
→ Corrosion resistance
What is Capacitor Foil?
Capacitor foil is ultra-thin, high-purity aluminum foil specially engineered for:
Energy storage in electrolytic capacitors,
Precision etching for increased surface area,
Stable electrical performance
Made from 99.6-99.9% pure aluminum with controlled surface treatments.
Why Choose Our Capacitor Foil?
IATF 16949 certified for automotive use
Custom etching profiles (tunnel, dendritic)
Strict thickness control (laser measurement)
Technical support for capacitor design
Packaging & Handling
- Standard:
- Vacuum-sealed moisture-proof bags
- 300mm plastic cores
- Export:
- Nitrogen-filled aluminum foil bags
- Humidity indicator cards included
- Labeling:
- Alloy/thickness
- Batch traceability code
Industry Standards Met
- IEC 60384-4 (Aluminum electrolytic capacitors)
- AEC-Q200 (Automotive qualification)
- RoHS/REACH compliant
Ordering Information
- Select alloy/thickness
- Specify etching requirements
- Provide formation voltage needs
- Receive technical datasheet
Minimum Order:
- 50kg for standard foils
- 200kg for custom etching
Conclusion
Capacitor foil is the unsung hero of modern electronics, enabling compact, high-performance energy storage from smartphones to electric vehicles. Selecting the right alloy and specifications ensures optimal capacitor reliability and efficiency.
Contact our engineers for application-specific recommendations!
