Checkout JEE MAINS 2022 Question Paper Analysis : Checkout JEE MAINS 2022 Question Paper Analysis :

# Electrolytic Capacitor

An electrolytic capacitor is a sort of capacitor that utilizes an electrolyte to obtain greater capacitance than the other type of capacitors. An electrolyte is a gel or fluid in which the concentration of ions is very high. An electrolytic capacitor is a general term used for three different capacitor family members:

• Aluminium electrolytic capacitors
• Tantalum electrolytic capacitors
• Niobium electrolytic capacitors

## Electrolytic Capacitors

Electrolytes are made up of aluminium or tantalum and a few other metals. Almost all the electrolytic capacitors are polarized, which means the voltage of the anode must always be higher than the cathode. The ability of large capacitance makes them highly useful for sending low-frequency signals. They are extensively used for noise filtering or decoupling in power supplies. The advantage of large capacitance comes with a few drawbacks as well. Drawbacks include leakage currents, equivalent series resistance, and a limited lifetime.

A special type of electrolytic capacitors with capacitances of hundreds and thousands of farads are known as supercapacitors. They are also known as double-layer electrolytic capacitors.

### Characteristics

#### Capacitance Drift:

The electrical characteristics depend highly on the electrolyte used and the anode. The capacitance of electrolytic capacitors has large tolerances of 20% and drifts from nominal value as time passes. This implies an aluminium capacitor whose nominal capacitance is 47µF and is expected to be between 37.6µF and 56.4µF.

Tantalum capacitors can also be made with higher tolerances, but their maximum operating voltage is low. So they cannot be used as perfect replacement aluminium capacitors.

Capacitance, Standard Values, and Tolerances:

The electrical characteristics depend highly on the electrolyte used and the anode. This affects the value of capacitance which again depends on temperature and frequency. The capacitors which contain non-solid electrolytes display a wide sense of temperature and frequency ranges than capacitors with a solid electrolyte. The base unit of the capacitance of an electrolytic capacitor is microfarad. The capacitance value that the manufacturers specify in the data sheets is called nominal capacitance or rated capacitance. The value of capacitance measured at the frequency of 1 kHz will be less by 10 per cent of 100/110 Hz and where the temperature is

$$\begin{array}{l}20^{\circ}C\end{array}$$
.

The percentage of allowed deviation of measured capacitance from the rated value is called the capacity tolerance. These capacitors are handy in a variety of tolerance series whose values are specified.

• rated capacitance, tolerance ±20%, Series E3, letter code “M”
• rated capacitance, tolerance ±20%, Series E6, letter code “M”
• rated capacitance, tolerance ±10%, Series E12, letter code “K”

### Applications

• Used to reduce voltage fluctuations in various filtering devices.
• Used in output and input smoothing to filter when the DC signal is weak with the AC component.
• They are extensively used for noise filtering or decoupling in power supplies.
• They are used for coupling signals between amplifier stages and also to store energy in flashlamps.

## Watch the video to learn how to solve problems on capacitors easily!

Stay tuned with BYJU’S to learn more about the electrolytic capacitor, types of capacitors, and much more.

## Frequently Asked Questions – FAQs

### What is capacitance?

Capacitance is the ratio of variation in the electric charge of an electrical system to the corresponding variation in its electrical potential.

### What is a capacitor?

A capacitor is an electrical component that has the capacity to store energy as electric charges. It comprises dual conductors that are separated by a considerable distance. The region between the conductors is generally filled with a dielectric (insulating material) or vacuum.

### What is the SI unit of capacitance?

The SI unit of capacitance is Farad.

### What is an electrolytic capacitor?

An electrolytic capacitor is a capacitor that uses an electrolyte to accumulate greater capacitance than other sorts of capacitors. It is a fluid or gel in which the density of ions is very high.

### Give one application of an electrolytic capacitor?

An electrolytic capacitor is used to decrease voltage variation in numerous filtering devices.
Test Your Knowledge On Electrolytic Capacitor!