Leclanche Cell

Leclanche Cell is a zinc-carbon battery known as a dry cell and is widely used in devices such as flashlights and portable zinc-manganese dioxide systems. It was initially used in telegraphy, signaling, and electric bell work.

In this article, we will see what Leclanche Cell is, its history, construction, applications, etc.

What is Leclanche Cell?

Leclanche Cell is a type of battery, a zinc-carbon primary cell that contains an electrolytic solution of ammonium chloride, a carbon cathode, a depolarizer of manganese dioxide, and an anode of zinc. The Leclanché cell is inexpensive to produce and provides a steady flow of electricity for a decent amount of time, making it popular due to its convenience and practicality.

However, more advanced battery technologies, such as alkaline and lithium-ion batteries, have largely replaced it.

Principle of Leclanche Cell

Principle of the Leclanche cell is based on the chemical reaction between the zinc anode and the manganese dioxide cathode in an electrolytic solution of ammonium chloride.

History of Leclanche Cell

Georges Leclanché, a French engineer, invented the Leclanche cell in 1866. This battery, initially containing a conducting solution of ammonium chloride, a carbon cathode, a manganese dioxide depolarizer, and a zinc anode, quickly succeeded in telegraphy, signaling, and electric bell work.

The cell’s design was later adapted to create more portable and efficient dry cells, such as the porous pot cell and the sack cell. Due to its low cost and practicality, it was a commercial success in large sizes and remained the least expensive dry cell for a significant period.

Leclanche Cell Diagram

Diagram of Leclanche Cell is shown below:

Leclanche Cell Construction

A Leclanche cell is constructed using a glass vessel filled with electrolyte of ammonium chloride solution. Let’s learn in detail about the components of leclanche and steps how to make it.

Components of Leclanche Cell

Materials required to construct a Leclanche cell are as follows:

• Anode: A zinc rod or a cylindrical can be made of a thin sheet of zinc, which serves as the anode and holds all other active and electrolyte materials of the battery
• Cathode: Carbon rod inserted into a porous pot containing a mixture of manganese dioxide and powdered carbon. The cathode is made of carbon mixed with manganese dioxide, which acts as a depolarizer.
• Electrolyte: Ammonium chloride solution, which acts as the conducting solution in the cell
• Porous pot: It contains the cathode and is used to hold the manganese dioxide and powdered carbon mixture.
• Supporting washer: Placed on top of the cathode bobbin.

Steps to Set Up Leclanche Cell

Steps to set up a Leclanche cell are,

Step 1: Take a glass vessel and fill it with ammonium chloride solution, which acts as an electrolyte.

Step 2: Place a zinc rod in the ammonium chloride solution. Zinc rod serves as anode.

Step 3: Fill a porous pot with a mixture of manganese dioxide and powdered carbon. Porous pot contains a carbon rod, which acts as cathode.

Step 4: Insert the porous pot into the glass vessel containing the ammonium chloride solution.

Step 5: Connect the zinc and carbon rods with a wire to complete the circuit.

Step 6: Leclanche cell is now set up and ready to use.

Note: Leclanche cell can also be set up in a dry cell form, which uses a paste electrolyte instead of a liquid one.

Working of a Leclanche cell

The working of leclanche cell can be understood in the terms of following chemical reactions:

• Zinc particles on the surface of the anode oxidize, releasing electrons and forming zinc ions in the electrolyte solution according to the following reaction:

Zn_(s) → Zn²⁺_(aq) + 2e⁻

• Released electrons flow through the external circuit and reach the cathode.
• At cathode, the ammonium ions in the electrolyte solution are reduced to molecular hydrogen and ammonia gas according to the following reaction:

2NH₄⁺_(aq) + 2e⁻ → 2NH_3(g) + H_2(g)

• Manganese dioxide in the cathode acts as a depolarizer, which absorbs the hydrogen ions and prevents the hydrogen gas from forming a layer on the cathode surface. The absorbed hydrogen ions react with the manganese dioxide to form water and manganese oxide according to the following reaction:

MnO_2(s) + 2NH₄⁺_(aq) + 2e⁻ → MnO(OH)_(s) + 2NH_3(g) + H₂O_(l)

• Overall reaction taking place in the Leclanche cell is:

Zn_(s) + 2MnO_2(s) + 2NH₄Cl_(aq) → ZnCl_2(aq) + Mn₂O_3(s) + 2NH_3(g) + H₂O_(l)

• Difference in the concentration of the zinc and hydrogen ions between the anode and cathode creates a potential difference, resulting in voltage production.
• Leclanche cell produces a voltage of around 1.5 volts and is commonly used in signaling networks and systems where a low current value is needed.

Difference between Leclanche Cell and Daniel Cell

Difference between Leclanche Cell and Daniel Cell is given below in table.

Leclanche Cell vs Daniel Cell
Features	Leclanche Cell	Daniel Cell
Electrodes	Leclanche cell contains a zinc anode and a carbon cathode with manganese dioxide	Daniel cell contains a zinc anode and a copper cathode
Electrolyte	It uses an electrolyte of ammonium chloride,	It uses a solution of copper sulfate and zinc sulfate
Working Principle	Leclanche cell operates by the oxidation of zinc at the anode and the reduction of manganese dioxide at the cathode.	Daniel cell operates by the oxidation of zinc at the anode and the reduction of copper at the cathode
Voltage	It produces a voltage of around 1.5 volts	It produces a voltage of around 1.08 volts
Durability	It is more durable	It is less durable

Applications of Leclanche cells

Some of applications of Leclanche cell are,

• Signaling Networks: Leclanche cell is widely used in signaling networks due to its ability to provide a steady flow of electricity for a decent amount of time
• Telegraphy: Leclanche cell was initially used in telegraphy, where it provided a voltage of 1.4 volts, making it suitable for transmitting electrical signals over long distances
• Early Telephones: Dry cell form of the Leclanche cell was used to power early telephones, usually from an adjacent wooden box affixed to the telephone
• Electric Bells: Leclanche cell was also used in electric bell work, where it provided a steady flow of electricity to power the bells

Read More,

• Electric Cell
• Electrochemical Cell
• Galvanic Cell

Leclanche Cell Frequently Asked Questions

How does Leclanche Cell Work?

Leclanche cell works through a chemical reaction between zinc and manganese dioxide, with an ammonium chloride solution acting as the electrolyte.

What is Voltage Produced by Leclanche Cell?

Voltage produced by a Leclanche cell is around 1.5 volts.

What is Construction of Leclanche Cell?

Construction of a Leclanche cell includes a zinc anode, a manganese dioxide cathode, and an ammonium chloride electrolyte in a porous pot.

What are Uses of Leclanche Cell?

Leclanche cells are commonly used in devices like flashlights and portable electronic gadgets.

How is Leclanche Cell different from Daniel Cell?

Unlike Daniel cell, a Leclanche cell is dry, making it more portable and suitable for everyday devices, while a Daniel cell uses a liquid electrolyte.

What is Leclanche Cell also Called?

Leclanche Cell is also called as Zinc Carbon Battery.

What is Example of Leclanche Cell?

Leclanche Cell is also called Dry Cell.