Automobile Engineering | Sketch a cut section showing construction of battery. Label the components and state their function.

Function of Battery,

1. Battery supplies the current for cranking motor and ignition system when the engine is being cranked for starting.  

2. When the vehicle is stationary battery supplies electricity for operating the various electrical devices.  

3. It is the secondary source of electrical energy when vehicle is not operating and generator speed is insufficient to meet the full load requirement.  

The main Components of Battery are

1. Container  

2. Plates 

3. Separators 

4. Electrolyte 

5. Cell Covers 

Construction of Battery

1. Container:

The container is made of acid resistance hard rubber or plastic. It is divided in to compartments. Each compartment form a cell of 2V. At the bottom of Container bridges are provided form space for sediment collection. This avoids the danger of short circuit.  

2. Plates: 

There are two types of battery plates positive & negative. Each plate is made of frame or Grid of an alloy of lead and antimony. The function of grid is to hold active material and carry the current. Active material in the positive plate grid is red lead (Pb3O4) and in the negative plate it is litharge (PbO).The negative plate group contain one plate more than the positive plate group.  

3. Separators:

To avoid the direct contact & thus short circuiting of positive & -ve plates thin sheet of some Non-conducting material inserted between them called separator.  

4. Cell Cover:

They are moulded from hard rubber . Each cell cover contains holes for positive and negative plate, a vent & filler opening. Vents are provided to escape the gases.  

5. Electrolyte:

After assembling completely the battery is filled with electrolyte. It is a solution of Sulphuric acid contains approximately one part of Sulphuric acid & two part of water by volume. specific gravity of Electrolyte is the measure of discharge of the battery. In the charge condition Sp.gr.is 1.290 where as in the discharge condition it is reduced to about 1.110.