BATTERY, CLASSIFICATION OF BATTERIES, PRIMARY, SECONDARY BATTERIES, DRY CELL OR LECLANCHE'S CELL

1. Dr. K. RAJENDER REDDY
LECTURER IN CHEMISTRY
Email: raj3iict@gmail.com
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2. Contents
• BATTERIES
1. Definition
2. A Battery to be practical use
3. Types of Batteries
4. Primary Battery, Examples
5. Secondary Battery, Examples
6. Dry Cell or Leclanche’s Cell
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3. Battery
• Definition: Two or more electrochemical cells
connected in a series is called battery.
• Battery is used as a source of direct electric
current.
• Cell contains only one anode and cathode,
where as battery contains many anodes and
cathodes.
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4. For a battery to be practical use
1. It should be light and compact
2. It’s voltage should not use vary appreciably
during its usage
3. It should have long life.
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5. Types of batteries
• Batteries are two types
1. Primary batteries
2. Secondary batteries
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6. Primary Battery or Primary Cell
• Definition: The cell in which the electrode
reactions can’t be reversed by passing an
external electrical energy is called primary
cell.
• i.e.: Non rechargeable batteries
• Ex: Dry cell, Mercury cell.
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7. Secondary battery or Secondary cell
• Definition: The cell in which the electrode
reaction can be reversed by passing an
external electrical energy is called secondary
cell.
• i.e: Rechargeable batteries
• These are also called as storage cell
• Ex: Lead storage cell, Ni-Cd cell
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8. Dry Cell or Leclanche’s cell (Video)
instruction: Double click on LOADING
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9. Dry Cell or Leclanches Cell
• Anode : Zn (container)
• Cathode : Carbon rod(Graphite) immersed
in electrolyte.
• Electrolyte: Powder of ammonium chloride+
Zinc Chloride and Manganese dioxide in the
form of paste using starch and water.
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10. Dry Cell or Leclanches Cell
• The reaction can be represented as:
• At anode: Zn Zn+2+2e-
• At cathode:
NH4
++MnO2+2e- MnO(OH)+NH3
• Over all reaction:
Zn +NH4
++MnO2 Zn+2 +MnO(OH)+NH3
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11. THANK YOU
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