Aluminum electrolytic capacitors are essential components in electrical products. Due to their superior performance, low cost, and wide range of applications, they have rapidly developed. The main aluminum foils used in capacitors include models such as 3003, 1100, and 1070.
Role of Aluminum Foil in Capacitors
Aluminum foil, as a key material in electrolytic capacitors, has the following characteristics:
- 1. Conductivity: Aluminum foil has excellent conductivity, making it suitable for the anode electrodes in capacitors.
- 2. Oxide Film: The surface of aluminum foil undergoes anodic oxidation treatment, forming an aluminum oxide (Al₂O₃) film that provides excellent dielectric properties. This oxide film has a higher dielectric constant than traditional materials, allowing it to store more electrons per unit area.
Specifications of Aluminum Foil for Electrolytic Capacitors
- Alloy: 3003, 1100, 1070
- State: H18
- Thickness: 0.02 - 0.055 mm
- Width: 100 - 1700 mm
- Application: Electrolytic capacitors
Chemical Composition of Aluminium Foil for Electrolytic Capacitors
Chemical Composition of 3003 Aluminum Foil for Electrolytic Capacitors
| Component | Content Range |
| Aluminum (Al) | 98.9% - 99.0% |
| Manganese (Mn) | 1.0% - 1.5% |
| Copper (Cu) | 0.05% - 0.20% |
| Silicon (Si) | 0.6% - 0.9% |
| Iron (Fe) | 0.7% - 1.2% |
| Magnesium (Mg) | 0.05% - 0.20% |
| Others | 0.05% (each element) |
| Remainder | Aluminum |
Chemical Composition of 1100 Aluminum Foil for Electrolytic Capacitors
| Component | Content Range |
| Aluminum (Al) | 99.0% - 99.7% |
| Copper (Cu) | 0.05% - 0.20% |
| Iron (Fe) | 0.0% - 0.35% |
| Silicon (Si) | 0.0% - 0.25% |
| Manganese (Mn) | 0.0% - 0.05% |
| Magnesium (Mg) | 0.0% - 0.05% |
| Others | 0.05% (each element) |
| Remainder | Aluminum |
Chemical Composition of 1070 Aluminum Foil for Electrolytic Capacitors
| Component | Content Range |
| Aluminum (Al) | 99.7% - 99.9% |
| Copper (Cu) | 0.0% - 0.05% |
| Iron (Fe) | 0.0% - 0.35% |
| Silicon (Si) | 0.0% - 0.25% |
| Manganese (Mn) | 0.0% - 0.05% |
| Magnesium (Mg) | 0.0% - 0.05% |
| Others | 0.05% (each element) |
| Remainder | Aluminum |
Structure and Working Principle of Aluminum Electrolytic Capacitors
Aluminum electrolytic capacitors are typically polarized electrolytic capacitors, and their main structure and working principle are as follows:
- Anode Electrode (+): Made from etched pure aluminum foil. The aluminum forms a thin aluminum oxide (Al₂O₃) insulation layer through anodization, which serves as the dielectric for the capacitor.
- Cathode Electrode (-): Formed by a non-solid electrolyte covering the rough surface of the oxide layer, it is in contact with the electrolyte and acts as the negative terminal of the capacitor.
Main Materials and Production Processes of Aluminum Electrolytic Capacitors
- Main Raw Materials: Anode aluminum foil, cathode aluminum foil, electrolyte paper, electrolyte, foil leads, tape, cover plates, aluminum cans, gaskets, etc.
- Production Processes: Includes aluminum foil preparation, forming, cutting, assembly, winding, impregnation, sealing, aging, measuring, packaging, and inspection.
Manufacturing and Treatment of Aluminum Foil for Electrolytic Capacitors
- Etching: Aluminum foil is treated in a chloride solution through an electrochemical etching process to increase its surface area. Etching is an electrochemical process using either alternating current or direct current.
- Formation: An insulating dielectric layer of aluminum oxide (Al₂O₃) is formed on the surface of the aluminum foil, typically by applying a voltage higher than the rated voltage in an ammonium borate solution. This oxide layer is very thin and dense, with a thickness of about 1 to 1.5 nm/V, and an insulation resistance between 10⁸ and 10⁹ Ω/m.
Advantages of Haomei Aluminum Foil for Electrolytic Capacitors
Haomei Aluminum produces foils, such as 3003, 1100, and 1070 aluminum foils, which offer a range of significant advantages, making them the preferred raw material supplier for electrolytic capacitor manufacturers.
1. Excellent Conductivity
Haomei Aluminum's foils exhibit outstanding conductivity in electrolytic capacitor applications. This is due to the high purity and low resistance of the aluminum alloys used, ensuring stable current conduction during capacitor operation, thus enhancing overall capacitor performance and reliability.
2. Superior Ductility
Our aluminum foils have extremely high ductility, meaning they can be processed into very thin foils during production without breaking. This high ductility ensures that the foils can be effectively wound into the required structures in capacitor manufacturing, increasing the capacitor's capacitance and efficiency.
3. Long Service Life
Haomei Aluminum's foils offer excellent corrosion resistance and stability, significantly extending the service life of electrolytic capacitors. Our foils maintain stable electrical performance over extended periods, reducing the risk of capacitor failure and consequently lowering maintenance costs and replacement frequency.
4. High-Quality Production Standards
Our production processes adhere to strict quality standards, ensuring that each roll of foil has consistent thickness, surface smoothness, and chemical composition. This consistency guarantees stability and reliability in the performance of electrolytic capacitors.
5. Direct Supply and Competitive Pricing
As a major manufacturer, Haomei Aluminum can supply high-quality foils directly, eliminating intermediary costs and offering competitive prices. Our customers benefit from high-quality foil materials and cost advantages, optimizing production costs and enhancing market competitiveness.
Haomei Aluminum's 3003, 1100, and 1070 foils, with their excellent conductivity, superior ductility, and long service life, have become indispensable choices for electrolytic capacitor manufacturers.