How do aluminum foil capacitors work?

A 0.05~0.11 mm thick anode foil and a 0.02~0.05 mm thick cathode foil are continuously etched electrochemically in a chloride solution with an AC or DC current. This enlarges the effective surface area of the aluminum foils to attain smaller capacitor sizes. The process develops aluminum oxide (Al203) to form a capacitor dielectric.

Can aluminum foil be used to etch a capacitor?

In comparison to other dielectric, similar voltage endurance is provided by dielectrics even if thickness ("d" in the above formula) is thin. By etching the surface of aluminum foil, the effective area of the foil can be enlarged 80~100 times for low voltage capacitors and 30~40 times for middle / high voltage capacitors.

What is a foil capacitor?

The so called foil capacitor has electrodes consisting of aluminum, 510 μm (0.20.4 mils) thick. Every turn in a capacitor winding adds at least 2×5 μm (2×0.2 mils) metal foil + dielectric which means that the electrodes in a low voltage capacitor accounts for the greater part of the volume.

How do you cut aluminum foil?

Step 1: Measure and Cut the Aluminum Foil. 1. Measure and cut 2 rectangular sections of Aluminum Foil measuring 6.5x10.5 inches (22.9x25.4 cm.) 2. Cut rectangular sections (1.5x5 in., 3.8x12.7 cm.) out of the aluminum sheets so there is a tab (1.5x1.5 in., 3.8x3.8 cm) sticking out of the top left corner of each piece. See above figure for example.

How do you charge a capacitor in a heavy book?

Place the connected capacitor underneath the Heavy Books. Note: This is done in order to flatten the aluminum sheets together and increase capacitance by decreasing distance between the sheets. Step 5: Charge the Capacitor. 1. Turn on the voltage source and wait about 30 seconds for the capacitor to fully charge. See above figure for example.

How to charge a capacitor?

1. Turn on the voltage source and wait about 30 seconds for the capacitor to fully charge. See above figure for example. Note: The time you have to wait varies with the capacitance and resistance, so using a smaller resistor will make the wait time significantly less. Note: The capacitor should reach the value of the input voltage.