# 12 Differences between Capacitor and Battery

What is Capacitor?

An electrical component that holds an electric charge is known as a capacitor. A capacitor consists of two closely spaced conductors (typically plates) separated by a dielectric substance. When the plates are linked to a power source, they acquire an electric charge. The positive charge builds on one plate, while the negative charge accumulates on the other.

What is capacitance?

At a voltage of 1 volt, the capacitance is the amount of electric charge stored in the capacitor.

The capacitance is measured in units of Farad (F).

In direct current (DC) circuits, the capacitor disconnects current and short circuits in alternating current (AC) circuits.

Capacitance

The capacitor’s capacitance © is calculated by dividing the electric charge (Q) by the voltage (V):

C= Capacitance (F)

Q= Electric charge stored in the capacitor

V= Voltage between the plates of the capacitor

Symbolic Representation of Capacitor

Capacitors in Series

Capacitors in Parallel

Types of Capacitors

• Film Capacitors
• CeramicCapacitors
• ElectrolyticCapacitors
• Variable Capacitors

What is capacitor coupling?

In a process known as Capacitor Coupling, capacitors allow AC to pass through while blocking DC. In the case of a loudspeaker, it is used. Speakers produce sound by converting an alternating current to a direct current, but any direct current that reaches them may cause damage. The direct current is protected from harming the speakers by a capacitor.

Difference between Alternator and Generator

Differences between Capacitor and Inductor

What is Battery?

A battery is an electronic component that is made up of either one cell or a couple of cells with an external connection to provide electrical power to the electrical device. A battery is referred to as an electric power source for electrical devices.

Every battery is made up of three following components. They are

• An Anode (‘-‘ side)
• A Cathode (‘+’ side)
• Electrolyte ( a substance that reacts with the anode and cathode)

Symbolic representation of battery

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How does the battery work?

A working principle of battery is based upon the reduction and oxidation reaction of an electrolyte with metals. A cathode is the negatively charged electrode due to the oxidation reaction and due to the reduction reaction, another electrode will get a positive charge and it is called an anode.

When the battery connected to a device or circuit, there is a chemical reaction occurs between the anode and electrolytes of the battery. The chemical reaction makes the flow of electrons through the circuit and returns back into the cathode of the battery where another chemical reaction occurs.

Capacitor Vs Battery

S.No Capacitor Battery
1 It is a passive component in a circuit It is referred to as the active component in a circuit
2 The potential energy is stored in the electric field The potential energy is stored in a form of chemical energy and converted it into electric energy when required
3 Lesser energy density than battery Higher energy density than capacitor
4 Charging and discharging happens quickly Charging and discharging happens slowly
5 Discharges instantaneously Runs for a longer time
6 Working based upon electrostatic field Working based on electrochemical reaction
7 It can store electrons only It can both store and generate electrons
8 Same polarity while charging and discharging occurs Battery has reversed polarity while charging and discharging
9 Long life span Short service life
10 Cheap and affordable Costly compared to capacitor
11 Can be used in electrical as well as electronic circuits or devices Can be used in electronic devices, medical devices, IoT devices, etc
12 Capacitors are classified into different types such as Ceramic, Tantalum, and Electrolytic. Batteries are classified into different types such as Alkaline, Lead-acid, Lithium-ion, Nickel-cadmium, Zinc-carbon.

Application of Capacitor

• Capacitor used in power supplies
• Capacitor can be used as a sensor to sense air humidity, fuel level, etc
• Removing glitches from direct current (DC) power rails

Application of Battery

• Batteries are used in various household equipment such as clocks, remote controls, torches, etc.
• Batteries are very much needed to medical equipment like electrocardiogram, glucose meters, infusion pumps, digital thermometers etc
• Batteries are required to power radio communication, night vision cameras, radars, various field devices, etc.

Differences between Conductor and Insulator

Some Useful Questions

1)What happens when you connect a capacitor to a battery?

When a capacitor is linked to a battery, a charge develops on both sides of the capacitor. In addition, there will be a current flow in the circuit for a short period of time until it drops to zero.

2) What is the emf of the dry cell?

The emf of the dry cell is 1.5 V.