Capacitor aluminum shell flange picture

What is the structure of aluminum electrolytic capacitor?

2. Structure of Aluminum Electrolytic Capacitor The aluminum electrolytic capacitor has, as shown in Fig.3 , a roll of anode foil, paper separator, cathode foil and electrode terminals (internal and external terminals) with the electrolyte impregnated, which is sealed in an aluminum can case with a sealing material.

How does the capacitance of an aluminum electrolytic capacitor increase?

Equation (1) shows that the capacitance (C) increases as the dielectric constant (ε) and/or its surface area (S) increases and/or the dielectric thickness (d) decreases. An aluminum electrolytic capacitor comprises a dielectric layer of aluminum oxide (Al 2 O 3 ), the dielectric constant (ε) of which is 8 to 10.

How do aluminum electrolytic capacitors work?

However, by extending the surface area (S) of the aluminum foil electrode by means of etching, and by electrochemically forming a thinner but highly voltage-withstandable layer of oxide layer dielectric, the aluminum electrolytic capacitor can offer a larger CV product per case size than other types of capacitors.

What is the dielectric constant of an aluminum electrolytic capacitor?

An aluminum electrolytic capacitor comprises a dielectric layer of aluminum oxide (Al 2 O 3 ), the dielectric constant (ε) of which is 8 to 10. This value is not significantly larger than those of other types of capacitors.

Are aluminum electrolytic capacitors polarized or asymmetrical?

In general, an aluminum electrolytic capacitor is asymmetrical in structure and polarized. The other capacitor type known as a bi-polar (non-polar) comprises the anodic aluminum foils for both electrodes. 2. Structure of Aluminum Electrolytic Capacitor

What is the etching process of cathode aluminum foil?

An etching process is performed to the cathode aluminum foil as well as the anode foil. However, the formation process for oxide layer is generally not performed. Therefore, the surface of the cathode foil only has an oxide layer (Al 2 O 3) that has spontaneously formed, which gives a withstand voltage of about 0.5 volt