Cell and Battery

A Cell
A cell is a very small battery. A good example is the type found in most modern watches. This type of battery is often used in camcorders as backup batteries. They ensure that the date and time are held in memory even when the rechargeable batteries are removed. Button batteries are usually rated at 1.5 volts or 3 volts and consequently they are used in devices that need very little power. Watches are ideal for this type of battery as well as low power calculators and hearing aids. Large button batteries are used as backup batteries for the CMOS of computer systems and ensure that the basic settings in the setup of the computer are held in memory, even when the computer is switched off.




This is how it looks




Battery
Batteries come in all shapes and sizes. They store electrical charge and as we all know when they are put into an electronic device such as a portable radio, they provide the power.most commonly used batteries are1.5 volts and 9 volts.
School projects are powered by batteries because they are safe, easily buy and safe.




Simple Circuit
This shows one of the most simple circuits. When the switch is pressed, the LED (further information below) lights. Resistors are used in circuits because LEDs can be destroyed by voltages over 3 volts. Why do you think the circuit opposite does not have a resistor to protect the LED ?

Each battery is 1.5 volts. The two batteries are connected in ‘series’, they are both linked positive to negative and this gives us a total of 3 volts. Therefore, the LED is safe from damage.




Same Circuit Using a CELL

Now in this circuit only when the circuit is closed the LED will Glow.

Posted in: circuit elements