220µF 25V capacitor is a high-quality electrolytic capacitor with long service life and reliability. In electronic circuits, electrolytic capacitors are the most commonly used capacitors. Electrolytic capacitors uses an electrolyte to achieve a higher capacitance than other capacitor types. An electrolyte is a liquid or gel that contains a large number of ions. Almost all electrolytic capacitors are polarized, which means the positive terminal voltage must always be larger than the negative terminal voltage. They are usually marked with a band on cathode side of the capacitor indicating the negative terminal.