WEE Technology Company Limited - WEE are Capacitors Specialist

The core of aluminum electrolytic capacitor is made of four layers of anode aluminum foil, electrolytic paper, cathode aluminum foil, electrolytic paper, etc. after the core contains electrolyte, it is sealed with aluminum shell and rubber cover to form an electrolytic capacitor. Compared with other types of capacitors, aluminum electrolytic capacitors have the following obvious characteristics in structure:

 (1) The working medium of aluminum electrolytic capacitor is to form a very thin layer of aluminum oxide (Al2O3) on the surface of aluminum foil by anodizing. The oxide medium layer and the anode of the capacitor are combined into a complete system, and they are interdependent and cannot be independent of each other. As we usually say, the electrode and dielectric of the capacitor are independent of each other.
 (2) The anode of aluminum electrolytic capacitor is the aluminum foil with Al2O3 dielectric layer on its surface. The cathode is not the negative foil we used to think, but the electrolyte of capacitor.
 (3) Negative foil plays the role of electrical lead-out in electrolytic capacitor, because the electrolyte as cathode of electrolytic capacitor can not be directly connected with the external circuit, it must form an electrical path through another metal electrode and other parts of the circuit.
 (4) The anode aluminum foil and cathode aluminum foil of aluminum electrolytic capacitor are usually corrosion aluminum foil. The actual surface area is much larger than its apparent surface area, which is also a reason why aluminum electrolytic capacitor usually has large capacitance. Due to the use of aluminum foil with many micro etched holes, liquid electrolyte is usually needed to make more effective use of its actual electrode area.
 (5) As the dielectric oxide film of aluminum electrolytic capacitor is obtained by anodizing, and its thickness is directly proportional to the voltage applied by anodizing, therefore, in principle, the thickness of dielectric layer of aluminum electrolytic capacitor can be accurately controlled as a technical reference